diff --git a/js/src/jsapi.cpp b/js/src/jsapi.cpp
index da5ae899b8c6..0488727b160a 100644
--- a/js/src/jsapi.cpp
+++ b/js/src/jsapi.cpp
@@ -933,7 +933,7 @@ JSRuntime::init(uint32_t maxbytes)
         return false;
     }
 
-    atomsCompartment->isSystemCompartment = true;
+    atomsCompartment->isSystem = true;
     atomsCompartment->setGCLastBytes(8192, GC_NORMAL);
 
     if (!InitAtoms(this))
diff --git a/js/src/jscompartment.cpp b/js/src/jscompartment.cpp
index 62fb1f2279f2..f9a973196bd6 100644
--- a/js/src/jscompartment.cpp
+++ b/js/src/jscompartment.cpp
@@ -64,7 +64,7 @@ JSCompartment::JSCompartment(JSRuntime *rt)
     gcTriggerBytes(0),
     gcHeapGrowthFactor(3.0),
     hold(false),
-    isSystemCompartment(false),
+    isSystem(false),
     lastCodeRelease(0),
     analysisLifoAlloc(LIFO_ALLOC_PRIMARY_CHUNK_SIZE),
     typeLifoAlloc(LIFO_ALLOC_PRIMARY_CHUNK_SIZE),
diff --git a/js/src/jscompartment.h b/js/src/jscompartment.h
index 45adbbdbb5ce..2a3fbf0a7ca0 100644
--- a/js/src/jscompartment.h
+++ b/js/src/jscompartment.h
@@ -335,7 +335,7 @@ struct JSCompartment : private JS::shadow::Zone, public js::gc::GraphNodeBase<JS
     double                       gcHeapGrowthFactor;
 
     bool                         hold;
-    bool                         isSystemCompartment;
+    bool                         isSystem;
 
     int64_t                      lastCodeRelease;
 
diff --git a/js/src/jsfriendapi.cpp b/js/src/jsfriendapi.cpp
index 721e80dc9cfd..d84e36fc95b7 100644
--- a/js/src/jsfriendapi.cpp
+++ b/js/src/jsfriendapi.cpp
@@ -218,7 +218,7 @@ JS_SetCompartmentPrincipals(JSCompartment *compartment, JSPrincipals *principals
         // with the old one, but JSPrincipals doesn't give us a way to do that.
         // But we can at least assert that we're not switching between system
         // and non-system.
-        JS_ASSERT(compartment->zone()->isSystemCompartment == isSystem);
+        JS_ASSERT(compartment->zone()->isSystem == isSystem);
     }
 
     // Set up the new principals.
@@ -228,7 +228,7 @@ JS_SetCompartmentPrincipals(JSCompartment *compartment, JSPrincipals *principals
     }
 
     // Update the system flag.
-    compartment->zone()->isSystemCompartment = isSystem;
+    compartment->zone()->isSystem = isSystem;
 }
 
 JS_FRIEND_API(JSBool)
@@ -318,7 +318,7 @@ AutoSwitchCompartment::~AutoSwitchCompartment()
 JS_FRIEND_API(bool)
 js::IsSystemCompartment(const JSCompartment *c)
 {
-    return c->zone()->isSystemCompartment;
+    return c->zone()->isSystem;
 }
 
 JS_FRIEND_API(bool)
diff --git a/js/src/jsgc.cpp b/js/src/jsgc.cpp
index 6c2b3c383b92..7326dc59c19b 100644
--- a/js/src/jsgc.cpp
+++ b/js/src/jsgc.cpp
@@ -676,7 +676,7 @@ static inline Chunk **
 GetAvailableChunkList(Zone *zone)
 {
     JSRuntime *rt = zone->rt;
-    return zone->isSystemCompartment
+    return zone->isSystem
            ? &rt->gcSystemAvailableChunkListHead
            : &rt->gcUserAvailableChunkListHead;
 }
diff --git a/js/src/jsmemorymetrics.cpp b/js/src/jsmemorymetrics.cpp
index 1a00e0209107..f59dc5c4c288 100644
--- a/js/src/jsmemorymetrics.cpp
+++ b/js/src/jsmemorymetrics.cpp
@@ -334,7 +334,7 @@ JS::SystemCompartmentCount(const JSRuntime *rt)
 {
     size_t n = 0;
     for (size_t i = 0; i < rt->compartments.length(); i++) {
-        if (rt->compartments[i]->zone()->isSystemCompartment)
+        if (rt->compartments[i]->zone()->isSystem)
             ++n;
     }
     return n;
@@ -345,7 +345,7 @@ JS::UserCompartmentCount(const JSRuntime *rt)
 {
     size_t n = 0;
     for (size_t i = 0; i < rt->compartments.length(); i++) {
-        if (!rt->compartments[i]->zone()->isSystemCompartment)
+        if (!rt->compartments[i]->zone()->isSystem)
             ++n;
     }
     return n;