diff --git a/docs/guide/exe_verilator.rst b/docs/guide/exe_verilator.rst
index 11add271f..766a1d09b 100644
--- a/docs/guide/exe_verilator.rst
+++ b/docs/guide/exe_verilator.rst
@@ -155,7 +155,7 @@ Summary:
    requires GNU Make to be available on the platform.
 
    :vlopt:`--build` cannot be specified when using :vlopt:`-E`,
-   :vlopt:`--dpi-hdr-only`, :vlopt:`--lint-only`, or :vlopt:`--xml-only`.
+   :vlopt:`--dpi-hdr-only`, :vlopt:`--json-only` or :vlopt:`--lint-only`.
 
 .. option:: --build-dep-bin <filename>
 
@@ -606,7 +606,7 @@ Summary:
 .. option:: --flatten
 
    Force flattening of the design's hierarchy, with all modules, tasks, and
-   functions inlined. Typically used with :vlopt:`--xml-only`.
+   functions inlined. Typically used with :vlopt:`--json-only`.
    Flattening large designs may require significant CPU time, memory and
    storage.
 
diff --git a/src/V3AstNodeDType.h b/src/V3AstNodeDType.h
index 4eafbbeae..3c80873fe 100644
--- a/src/V3AstNodeDType.h
+++ b/src/V3AstNodeDType.h
@@ -957,7 +957,7 @@ class AstMemberDType final : public AstNodeDType {
     //
     // @astgen ptr := m_refDTypep : Optional[AstNodeDType]  // Elements of this type (post-width)
     string m_name;  // Name of variable
-    string m_tag;  // Holds the string of the verilator tag -- used in XML output.
+    string m_tag;  // Holds the string of the verilator tag -- used in JSON output.
     int m_lsb = -1;  // Within this level's packed struct, the LSB of the first bit of the member
     bool m_constrainedRand = false;
     // UNSUP: int m_randType;    // Randomization type (IEEE)
diff --git a/src/V3AstNodeOther.h b/src/V3AstNodeOther.h
index e91ad41da..fe0c53525 100644
--- a/src/V3AstNodeOther.h
+++ b/src/V3AstNodeOther.h
@@ -1737,7 +1737,7 @@ class AstTypedef final : public AstNode {
     // @astgen op4 := attrsp : List[AstNode] // Attributes during early parse
 
     string m_name;
-    string m_tag;  // Holds the string of the verilator tag -- used in XML output.
+    string m_tag;  // Holds the string of the verilator tag -- used in JSON output.
     uint32_t m_declTokenNum;  // Declaration token number
     bool m_attrPublic = false;
     bool m_isHideLocal : 1;  // Verilog local
@@ -1866,13 +1866,13 @@ class AstVar final : public AstNode {
 
     string m_name;  // Name of variable
     string m_origName;  // Original name before dot addition
-    string m_tag;  // Holds the string of the verilator tag -- used in XML output.
+    string m_tag;  // Holds the string of the verilator tag -- used in JSON output.
     VVarType m_varType;  // Type of variable
     VDirection m_direction;  // Direction input/output etc
     VDirection m_declDirection;  // Declared direction input/output etc
     VLifetime m_lifetime;  // Lifetime
     VRandAttr m_rand;  // Randomizability of this variable (rand, randc, etc)
-    int m_pinNum = 0;  // For XML, if non-zero the connection pin number
+    int m_pinNum = 0;  // For JSON, if non-zero the connection pin number
     bool m_ansi : 1;  // Params or pins declared in the module header, rather than the body
     bool m_declTyped : 1;  // Declared as type (for dedup check)
     bool m_tristate : 1;  // Inout or triwire or trireg
diff --git a/src/V3LinkDot.cpp b/src/V3LinkDot.cpp
index a3c62b46d..ce83b9083 100644
--- a/src/V3LinkDot.cpp
+++ b/src/V3LinkDot.cpp
@@ -47,7 +47,7 @@
 //      ResolveVisitor:
 //          #9: Resolve general variables, which may point into the interface or modport (after #8)
 //      LinkResolve:
-//          #10: Unlink modports, not needed later except for XML/Lint
+//          #10: Unlink modports, not needed later except for JSON/Lint
 //*************************************************************************
 // TOP
 //      {name-of-top-modulename}
@@ -2205,7 +2205,7 @@ class LinkDotParamVisitor final : public VNVisitor {
             symp->exported(false);
             refp->pinNum(nodep->pinNum());
             // Put the variable where the port is, so that variables stay
-            // in pin number sorted order. Otherwise hierarchical or XML
+            // in pin number sorted order. Otherwise hierarchical or JSON
             // may botch by-position instances.
             nodep->addHereThisAsNext(refp->unlinkFrBack());
         }
diff --git a/src/V3LinkResolve.cpp b/src/V3LinkResolve.cpp
index 6e362411a..0aa8d460a 100644
--- a/src/V3LinkResolve.cpp
+++ b/src/V3LinkResolve.cpp
@@ -484,7 +484,7 @@ class LinkResolveVisitor final : public VNVisitor {
         iterateChildren(nodep);
     }
     //  void visit(AstModport* nodep) override { ... }
-    // We keep Modport's themselves around for XML dump purposes
+    // We keep Modport's themselves around for JSON dump purposes
 
     void visit(AstGenFor* nodep) override {
         VL_RESTORER(m_underGenerate);
diff --git a/src/V3Scope.cpp b/src/V3Scope.cpp
index 16a3d8014..4739883db 100644
--- a/src/V3Scope.cpp
+++ b/src/V3Scope.cpp
@@ -367,7 +367,7 @@ class ScopeCleanupVisitor final : public VNVisitor {
         iterateChildren(nodep);
     }
     void visit(AstModportFTaskRef* nodep) override {
-        // The modport persists only for xml dump
+        // The modport persists only for JSON dump
         // The crossrefs are dealt with in V3LinkDot
         nodep->ftaskp(nullptr);
         iterateChildren(nodep);
diff --git a/src/V3VariableOrder.cpp b/src/V3VariableOrder.cpp
index 7560fc01d..416d56c54 100644
--- a/src/V3VariableOrder.cpp
+++ b/src/V3VariableOrder.cpp
@@ -282,7 +282,7 @@ void V3VariableOrder::orderAll(AstNetlist* netlistp) {
     if (v3Global.opt.stats()) V3Stats::statsStage("variableorder-sort");
 
     // Insert them back under the module, in the new order, but at
-    // the front of the list so they come out first in dumps/XML.
+    // the front of the list so they come out first in dumps/JSON.
     for (AstNodeModule* modp = v3Global.rootp()->modulesp(); modp;
          modp = VN_AS(modp->nextp(), NodeModule)) {
         const std::vector<AstVar*>& varps = sortedVars[modp];
diff --git a/src/Verilator.cpp b/src/Verilator.cpp
index 3043c0c71..38229cdef 100644
--- a/src/Verilator.cpp
+++ b/src/Verilator.cpp
@@ -138,7 +138,7 @@ static void emitJson() VL_MT_DISABLED {
     v3Global.rootp()->dumpTreeJsonFile(filename);
 }
 
-static void emitXmlOrJson() VL_MT_DISABLED {
+static void emitSerialized() VL_MT_DISABLED {
     if (v3Global.opt.xmlOnly()) V3EmitXml::emitxml();
     if (v3Global.opt.jsonOnly()) emitJson();
 }
@@ -216,7 +216,7 @@ static void process() {
         VlOs::DeltaWallTime cvtWallTime{true};
         if (v3Global.opt.debugExitElab()) {
             V3Error::abortIfErrors();
-            if (v3Global.opt.serializeOnly()) emitXmlOrJson();
+            if (v3Global.opt.serializeOnly()) emitSerialized();
             cout << "--debug-exit-elab: Exiting after elaboration pass\n";
             v3Global.vlExit(0);
         }
@@ -634,7 +634,7 @@ static void process() {
         V3EmitC::emitcImp();
     }
     if (v3Global.opt.serializeOnly()) {
-        emitXmlOrJson();
+        emitSerialized();
     } else if (v3Global.opt.debugCheck() && !v3Global.opt.lintOnly()
                && !v3Global.opt.dpiHdrOnly()) {
         // Check XML/JSON when debugging to make sure no missing node types