diff --git a/compiler/testData/asJava/lightClasses/nullabilityAnnotations/ClassObjectField.java b/compiler/testData/asJava/lightClasses/nullabilityAnnotations/ClassObjectField.java
index e9e8f6be3c3..a2260c4be27 100644
--- a/compiler/testData/asJava/lightClasses/nullabilityAnnotations/ClassObjectField.java
+++ b/compiler/testData/asJava/lightClasses/nullabilityAnnotations/ClassObjectField.java
@@ -2,16 +2,16 @@ public final class ClassObjectField implements kotlin.jvm.internal.KObject {
     @org.jetbrains.annotations.Nullable
     public static final java.lang.String x = "";
     private static final java.lang.String y = "";
-    public static final ClassObjectField.object OBJECT$;
+    public static final ClassObjectField.Default Default;
 
     public ClassObjectField() { /* compiled code */ }
 
-    public static final class object implements kotlin.jvm.internal.KObject {
+    public static final class Default implements kotlin.jvm.internal.KObject {
         @org.jetbrains.annotations.Nullable
         public final java.lang.String getX() { /* compiled code */ }
 
         private final java.lang.String getY() { /* compiled code */ }
 
-        private object() { /* compiled code */ }
+        private Default() { /* compiled code */ }
     }
-}
+}
\ No newline at end of file
diff --git a/compiler/testData/asJava/lightClasses/nullabilityAnnotations/TraitClassObjectField.java b/compiler/testData/asJava/lightClasses/nullabilityAnnotations/TraitClassObjectField.java
index e62e588f3de..72bc3eaef1d 100644
--- a/compiler/testData/asJava/lightClasses/nullabilityAnnotations/TraitClassObjectField.java
+++ b/compiler/testData/asJava/lightClasses/nullabilityAnnotations/TraitClassObjectField.java
@@ -1,9 +1,9 @@
 public interface TraitClassObjectField {
-    TraitClassObjectField.object OBJECT$;
+    TraitClassObjectField.Default Default;
     @org.jetbrains.annotations.Nullable
     java.lang.String x = "";
 
-    static final class object implements kotlin.jvm.internal.KObject {
+    static final class Default implements kotlin.jvm.internal.KObject {
         @org.jetbrains.annotations.Nullable
         private final java.lang.String x = "";
         private final java.lang.String y = "";
@@ -13,6 +13,6 @@ public interface TraitClassObjectField {
 
         private final java.lang.String getY() { /* compiled code */ }
 
-        private object() { /* compiled code */ }
+        private Default() { /* compiled code */ }
     }
-}
+}
\ No newline at end of file
diff --git a/compiler/testData/codegen/box/classes/classObjectToString.kt b/compiler/testData/codegen/box/classes/classObjectToString.kt
index b6fdee98c38..cc4f4db1ceb 100644
--- a/compiler/testData/codegen/box/classes/classObjectToString.kt
+++ b/compiler/testData/codegen/box/classes/classObjectToString.kt
@@ -1,7 +1,7 @@
 class SomeClass { class object }
 
 fun box() = 
-    if ((SomeClass.toString() as java.lang.String).matches("SomeClass\\\$object@[0-9a-fA-F]+"))
+    if ((SomeClass.toString() as java.lang.String).matches("SomeClass\\\$Default@[0-9a-fA-F]+"))
         "OK"
     else
         "Fail: $SomeClass"
diff --git a/compiler/testData/codegen/boxWithStdlib/native/nativePropertyAccessors.kt b/compiler/testData/codegen/boxWithStdlib/native/nativePropertyAccessors.kt
index d9b18bb1b4b..f13b4e3fea2 100644
--- a/compiler/testData/codegen/boxWithStdlib/native/nativePropertyAccessors.kt
+++ b/compiler/testData/codegen/boxWithStdlib/native/nativePropertyAccessors.kt
@@ -39,8 +39,8 @@ fun box(): String {
     return check({defaultGetter}, "_DefaultPackage.getDefaultGetter()I")
            ?: check({defaultSetter = 1}, "_DefaultPackage.setDefaultSetter(I)V")
 
-           ?: check({C.defaultGetter}, "C\$object.getDefaultGetter()I")
-           ?: check({C.defaultSetter = 1}, "C\$object.setDefaultSetter(I)V")
+           ?: check({C.defaultGetter}, "C\$Default.getDefaultGetter()I")
+           ?: check({C.defaultSetter = 1}, "C\$Default.setDefaultSetter(I)V")
 
            ?: check({C().defaultGetter}, "C.getDefaultGetter()I")
            ?: check({C().defaultSetter = 1}, "C.setDefaultSetter(I)V")
diff --git a/compiler/testData/codegen/defaultArguments/reflection/classInClassObject.kt b/compiler/testData/codegen/defaultArguments/reflection/classInClassObject.kt
index c4fbf1f31a2..99cdd59209c 100644
--- a/compiler/testData/codegen/defaultArguments/reflection/classInClassObject.kt
+++ b/compiler/testData/codegen/defaultArguments/reflection/classInClassObject.kt
@@ -4,5 +4,5 @@ class A {
     }
 }
 
-// CLASS: A$object$Foo
+// CLASS: A$Default$Foo
 // HAS_DEFAULT_CONSTRUCTOR: true
diff --git a/compiler/testData/codegen/outerClassInfo/outerClassInfo.java b/compiler/testData/codegen/outerClassInfo/outerClassInfo.java
index f60a3716288..97a3dc84f9b 100644
--- a/compiler/testData/codegen/outerClassInfo/outerClassInfo.java
+++ b/compiler/testData/codegen/outerClassInfo/outerClassInfo.java
@@ -4,7 +4,7 @@ import java.lang.Object;
 
 class Foo {
 
-    class object { }
+    class Default { }
 
     class InnerClass { }
 
diff --git a/compiler/tests/org/jetbrains/kotlin/asJava/KotlinLightClassCoherenceTest.java b/compiler/tests/org/jetbrains/kotlin/asJava/KotlinLightClassCoherenceTest.java
index 0182d08a374..41561652390 100644
--- a/compiler/tests/org/jetbrains/kotlin/asJava/KotlinLightClassCoherenceTest.java
+++ b/compiler/tests/org/jetbrains/kotlin/asJava/KotlinLightClassCoherenceTest.java
@@ -23,6 +23,7 @@ import com.intellij.psi.PsiModifier;
 import com.intellij.psi.search.GlobalSearchScope;
 import junit.framework.ComparisonFailure;
 import org.jetbrains.annotations.NotNull;
+import org.jetbrains.kotlin.name.SpecialNames;
 
 import java.io.File;
 import java.lang.reflect.InvocationTargetException;
@@ -206,6 +207,6 @@ public class KotlinLightClassCoherenceTest extends KotlinAsJavaTestBase {
     }
 
     public void testClassObject() throws Exception {
-        doTest("test.WithClassObject.object");
+        doTest("test.WithClassObject." + SpecialNames.DEFAULT_NAME_FOR_DEFAULT_OBJECT.asString());
     }
 }
diff --git a/compiler/tests/org/jetbrains/kotlin/asJava/KotlinLightClassStructureTest.java b/compiler/tests/org/jetbrains/kotlin/asJava/KotlinLightClassStructureTest.java
index 68b04d84910..c70719ad3e0 100644
--- a/compiler/tests/org/jetbrains/kotlin/asJava/KotlinLightClassStructureTest.java
+++ b/compiler/tests/org/jetbrains/kotlin/asJava/KotlinLightClassStructureTest.java
@@ -25,6 +25,7 @@ import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 import org.jetbrains.kotlin.codegen.forTestCompile.ForTestCompileRuntime;
 import org.jetbrains.kotlin.config.CompilerConfiguration;
+import org.jetbrains.kotlin.name.SpecialNames;
 
 import java.io.File;
 import java.util.Arrays;
@@ -139,7 +140,7 @@ public abstract class KotlinLightClassStructureTest extends KotlinAsJavaTestBase
         }
 
         public void testInClassObjectActual() throws Exception {
-            checkMethodGenericParameter("test.PlatformStaticClass.object", "inClassObject", 0, "T");
+            checkMethodGenericParameter("test.PlatformStaticClass." + SpecialNames.DEFAULT_NAME_FOR_DEFAULT_OBJECT.asString(), "inClassObject", 0, "T");
         }
 
         public void testInClass() throws Exception {
diff --git a/compiler/tests/org/jetbrains/kotlin/codegen/OuterClassGenTest.java b/compiler/tests/org/jetbrains/kotlin/codegen/OuterClassGenTest.java
index 1ba041662e6..3db18635941 100644
--- a/compiler/tests/org/jetbrains/kotlin/codegen/OuterClassGenTest.java
+++ b/compiler/tests/org/jetbrains/kotlin/codegen/OuterClassGenTest.java
@@ -23,6 +23,7 @@ import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 import org.jetbrains.kotlin.backend.common.output.OutputFile;
 import org.jetbrains.kotlin.backend.common.output.OutputFileCollection;
+import org.jetbrains.kotlin.name.SpecialNames;
 import org.jetbrains.kotlin.test.ConfigurationKind;
 import org.jetbrains.org.objectweb.asm.ClassReader;
 import org.jetbrains.org.objectweb.asm.ClassVisitor;
@@ -43,7 +44,7 @@ public class OuterClassGenTest extends CodegenTestCase {
     }
 
     public void testClassObject() throws Exception {
-        doTest("foo.Foo$object", "outerClassInfo");
+        doTest("foo.Foo$" + SpecialNames.DEFAULT_NAME_FOR_DEFAULT_OBJECT.asString(), "outerClassInfo");
     }
 
     public void testInnerClass() throws Exception {
diff --git a/idea/testData/completion/injava/ClassObject.java b/idea/testData/completion/injava/ClassObject.java
index 4c0c7b014cb..506ebb0bbc3 100644
--- a/idea/testData/completion/injava/ClassObject.java
+++ b/idea/testData/completion/injava/ClassObject.java
@@ -1,6 +1,6 @@
 public class Testing {
     public static void test() {
-        mockLib.foo.LibClass.OBJECT$.<caret>
+        mockLib.foo.LibClass.Default.<caret>
     }
 }
 
diff --git a/idea/testData/completion/injava/NestedObjectInstance.java b/idea/testData/completion/injava/NestedObjectInstance.java
index 8d460fec507..88f97923c3c 100644
--- a/idea/testData/completion/injava/NestedObjectInstance.java
+++ b/idea/testData/completion/injava/NestedObjectInstance.java
@@ -1,6 +1,6 @@
 public class Testing {
     public static void test() {
-        mockLib.foo.LibClass.object.NestedObject.<caret>
+        mockLib.foo.LibClass.Default.NestedObject.<caret>
     }
 }
 
diff --git a/idea/testData/completion/injava/ObjectInClassObjects.java b/idea/testData/completion/injava/ObjectInClassObjects.java
index 2e4379c1d2b..6f350affb7c 100644
--- a/idea/testData/completion/injava/ObjectInClassObjects.java
+++ b/idea/testData/completion/injava/ObjectInClassObjects.java
@@ -1,6 +1,6 @@
 public class Testing {
     public static void test() {
-        mockLib.foo.F.object.F.object.<caret>
+        mockLib.foo.F.Default.F.Default.<caret>
     }
 }
 
diff --git a/idea/testData/debugger/positionManager/classObject.kt b/idea/testData/debugger/positionManager/classObject.kt
index 1a5c5c81864..fc8baf791f7 100644
--- a/idea/testData/debugger/positionManager/classObject.kt
+++ b/idea/testData/debugger/positionManager/classObject.kt
@@ -5,7 +5,7 @@ class A {
             1 + 1 // A
             val a = 1 // A
             fun foo() {
-                1 // A\$object\$1
+                1 // A\$Default\$1
             }
         }
 
@@ -13,23 +13,23 @@ class A {
 
         val prop2: Int
             get() {
-                val a = 1 + 1  // A\$object
-                return 1 // A\$object
+                val a = 1 + 1  // A\$Default
+                return 1 // A\$Default
             }
 
         val prop3: Int
-            get() = 1 // A\$object
+            get() = 1 // A\$Default
 
-        fun foo() = 1 // A\$object
+        fun foo() = 1 // A\$Default
 
         fun foo2() {
-            ""   // A\$object
+            ""   // A\$Default
 
             val o = object {
-                val p = 1 // A\$object\$foo2\$o\$1
+                val p = 1 // A\$Default\$foo2\$o\$1
                 val p2: Int
                     get() {
-                        return 1 // A\$object\$foo2\$o\$1
+                        return 1 // A\$Default\$foo2\$o\$1
                     }
             }
         }
@@ -38,6 +38,6 @@ class A {
 
 trait T {
     class object {
-        val prop = 1 // T\$object
+        val prop = 1 // T\$Default
     }
 }
diff --git a/idea/testData/findUsages/kotlin/findPropertyUsages/javaClassObjectPropertyUsages.1.java b/idea/testData/findUsages/kotlin/findPropertyUsages/javaClassObjectPropertyUsages.1.java
index 08523ad1d3c..f70bbf22ed8 100644
--- a/idea/testData/findUsages/kotlin/findPropertyUsages/javaClassObjectPropertyUsages.1.java
+++ b/idea/testData/findUsages/kotlin/findPropertyUsages/javaClassObjectPropertyUsages.1.java
@@ -4,9 +4,9 @@ import server.*;
 
 class Client {
     void fooBar() {
-        A.OBJECT$.setFoo("a");
+        A.Default.setFoo("a");
         A.foo = "a";
-        System.out.println("a.foo = " + A.OBJECT$.getFoo());
+        System.out.println("a.foo = " + A.Default.getFoo());
         System.out.println("a.foo = " + A.foo);
     }
 }
\ No newline at end of file
diff --git a/idea/testData/findUsages/kotlin/findPropertyUsages/javaClassObjectPropertyUsages.results.txt b/idea/testData/findUsages/kotlin/findPropertyUsages/javaClassObjectPropertyUsages.results.txt
index 58631d93115..4e40c422af3 100644
--- a/idea/testData/findUsages/kotlin/findPropertyUsages/javaClassObjectPropertyUsages.results.txt
+++ b/idea/testData/findUsages/kotlin/findPropertyUsages/javaClassObjectPropertyUsages.results.txt
@@ -1,4 +1,4 @@
 Unclassified usage (10: 43) System.out.println("a.foo = " + A.foo);
-Unclassified usage (7: 19) A.OBJECT$.setFoo("a");
+Unclassified usage (7: 19) A.Default.setFoo("a");
 Unclassified usage (8: 11) A.foo = "a";
-Unclassified usage (9: 51) System.out.println("a.foo = " + A.OBJECT$.getFoo());
\ No newline at end of file
+Unclassified usage (9: 51) System.out.println("a.foo = " + A.Default.getFoo());
\ No newline at end of file
diff --git a/idea/testData/hierarchy/class/type/ClassInClassObject/ClassInClassObject_verification.xml b/idea/testData/hierarchy/class/type/ClassInClassObject/ClassInClassObject_verification.xml
index 7fe91201793..01ae4b4a638 100644
--- a/idea/testData/hierarchy/class/type/ClassInClassObject/ClassInClassObject_verification.xml
+++ b/idea/testData/hierarchy/class/type/ClassInClassObject/ClassInClassObject_verification.xml
@@ -1,3 +1,3 @@
 <node text="Object (java.lang)">
-  <node text="MyClass in object in A ()" base="true"/>
+  <node text="MyClass in Default in A ()" base="true"/>
 </node>
\ No newline at end of file
diff --git a/idea/testData/resolve/referenceInJava/ClassObjectField.java b/idea/testData/resolve/referenceInJava/ClassObjectField.java
index fa8a730dae7..2c3257ee933 100644
--- a/idea/testData/resolve/referenceInJava/ClassObjectField.java
+++ b/idea/testData/resolve/referenceInJava/ClassObjectField.java
@@ -1,6 +1,6 @@
 public class ClassObjectField {
     public static void foo() {
-        k.ClassWithClassObject.OB<caret>JECT$.f();
+        k.ClassWithClassObject.De<caret>fault.f();
     }
 }
 
diff --git a/jps-plugin/testData/incremental/pureKotlin/classObjectConstantChanged/build.log b/jps-plugin/testData/incremental/pureKotlin/classObjectConstantChanged/build.log
index f277b681fb5..1049b7f2a22 100644
--- a/jps-plugin/testData/incremental/pureKotlin/classObjectConstantChanged/build.log
+++ b/jps-plugin/testData/incremental/pureKotlin/classObjectConstantChanged/build.log
@@ -1,12 +1,12 @@
 Cleaning output files:
-out/production/module/test/Klass$object.class
+out/production/module/test/Klass$Default.class
 out/production/module/test/Klass.class
 End of files
 Compiling files:
 src/const.kt
 End of files
 Cleaning output files:
-out/production/module/test/Klass$object.class
+out/production/module/test/Klass$Default.class
 out/production/module/test/Klass.class
 out/production/module/test/Usage.class
 End of files
diff --git a/jps-plugin/testData/incremental/pureKotlin/constantsUnchanged/build.log b/jps-plugin/testData/incremental/pureKotlin/constantsUnchanged/build.log
index e7a3af58bd6..cce56fbf9fd 100644
--- a/jps-plugin/testData/incremental/pureKotlin/constantsUnchanged/build.log
+++ b/jps-plugin/testData/incremental/pureKotlin/constantsUnchanged/build.log
@@ -1,5 +1,5 @@
 Cleaning output files:
-out/production/module/test/Klass$object.class
+out/production/module/test/Klass$Default.class
 out/production/module/test/Klass.class
 out/production/module/test/TestPackage$const$*.class
 out/production/module/test/TestPackage.class
diff --git a/jps-plugin/testData/incremental/pureKotlin/traitClassObjectConstantChanged/build.log b/jps-plugin/testData/incremental/pureKotlin/traitClassObjectConstantChanged/build.log
index 66a82a4119c..01ea0f084d3 100644
--- a/jps-plugin/testData/incremental/pureKotlin/traitClassObjectConstantChanged/build.log
+++ b/jps-plugin/testData/incremental/pureKotlin/traitClassObjectConstantChanged/build.log
@@ -1,6 +1,6 @@
 Cleaning output files:
 out/production/module/test/Trait$$TImpl.class
-out/production/module/test/Trait$object.class
+out/production/module/test/Trait$Default.class
 out/production/module/test/Trait.class
 End of files
 Compiling files:
@@ -8,7 +8,7 @@ src/const.kt
 End of files
 Cleaning output files:
 out/production/module/test/Trait$$TImpl.class
-out/production/module/test/Trait$object.class
+out/production/module/test/Trait$Default.class
 out/production/module/test/Trait.class
 out/production/module/test/Usage.class
 End of files
diff --git a/jps-plugin/testData/incremental/withJava/kotlinUsedInJava/constantChanged/build.log b/jps-plugin/testData/incremental/withJava/kotlinUsedInJava/constantChanged/build.log
index 78e27d0e4e4..d7a173db691 100644
--- a/jps-plugin/testData/incremental/withJava/kotlinUsedInJava/constantChanged/build.log
+++ b/jps-plugin/testData/incremental/withJava/kotlinUsedInJava/constantChanged/build.log
@@ -1,5 +1,5 @@
 Cleaning output files:
-out/production/module/test/Klass$object.class
+out/production/module/test/Klass$Default.class
 out/production/module/test/Klass.class
 End of files
 Compiling files:
@@ -7,7 +7,7 @@ src/const.kt
 End of files
 Cleaning output files:
 out/production/module/Usage.class
-out/production/module/test/Klass$object.class
+out/production/module/test/Klass$Default.class
 out/production/module/test/Klass.class
 End of files
 Compiling files:
diff --git a/jps-plugin/testData/incremental/withJava/kotlinUsedInJava/constantUnchanged/build.log b/jps-plugin/testData/incremental/withJava/kotlinUsedInJava/constantUnchanged/build.log
index 026ae147f5a..6bc3a50bee0 100644
--- a/jps-plugin/testData/incremental/withJava/kotlinUsedInJava/constantUnchanged/build.log
+++ b/jps-plugin/testData/incremental/withJava/kotlinUsedInJava/constantUnchanged/build.log
@@ -1,5 +1,5 @@
 Cleaning output files:
-out/production/module/test/Klass$object.class
+out/production/module/test/Klass$Default.class
 out/production/module/test/Klass.class
 End of files
 Compiling files: