diff --git a/Marlin/src/HAL/STM32F1/MarlinSerial.cpp b/Marlin/src/HAL/STM32F1/MarlinSerial.cpp
index 8c68a2de7f..8c468e9609 100644
--- a/Marlin/src/HAL/STM32F1/MarlinSerial.cpp
+++ b/Marlin/src/HAL/STM32F1/MarlinSerial.cpp
@@ -75,7 +75,7 @@ static __always_inline void my_usart_irq(ring_buffer *rb, ring_buffer *wb, usart
 }
 
 // Not every MarlinSerial port should handle emergency parsing.
-// It would not make sense to parse GCode from TMC responses, for example.
+// It would not make sense to parse G-Code from TMC responses, for example.
 constexpr bool serial_handles_emergency(int port) {
   return (false
     #ifdef SERIAL_PORT
diff --git a/Marlin/src/gcode/calibrate/G28.cpp b/Marlin/src/gcode/calibrate/G28.cpp
index fd034f0ba6..531dc5b558 100644
--- a/Marlin/src/gcode/calibrate/G28.cpp
+++ b/Marlin/src/gcode/calibrate/G28.cpp
@@ -536,7 +536,7 @@ void GcodeSuite::G28() {
     /**
      * Preserve DXC mode across a G28 for IDEX printers in DXC_DUPLICATION_MODE.
      * This is important because it lets a user use the LCD Panel to set an IDEX Duplication mode, and
-     * then print a standard GCode file that contains a single print that does a G28 and has no other
+     * then print a standard G-Code file that contains a single print that does a G28 and has no other
      * IDEX specific commands in it.
      */
     #if ENABLED(DUAL_X_CARRIAGE)
diff --git a/Marlin/src/gcode/control/M42.cpp b/Marlin/src/gcode/control/M42.cpp
index 6e75ffd4e7..13965cb72c 100644
--- a/Marlin/src/gcode/control/M42.cpp
+++ b/Marlin/src/gcode/control/M42.cpp
@@ -44,7 +44,7 @@ void protected_pin_err() {
 }
 
 /**
- * M42: Change pin status via GCode
+ * M42: Change pin status via G-Code
  *
  *  P<pin>  Pin number (LED if omitted)
  *          For LPC1768 specify pin P1_02 as M42 P102,
diff --git a/Marlin/src/gcode/feature/mixing/M163-M165.cpp b/Marlin/src/gcode/feature/mixing/M163-M165.cpp
index a4cb64e7d6..f4ea52df0a 100644
--- a/Marlin/src/gcode/feature/mixing/M163-M165.cpp
+++ b/Marlin/src/gcode/feature/mixing/M163-M165.cpp
@@ -76,7 +76,7 @@ void GcodeSuite::M164() {
    *   I[factor] Mix factor for extruder stepper 6
    */
   void GcodeSuite::M165() {
-    // Get mixing parameters from the GCode
+    // Get mixing parameters from the G-Code
     // The total "must" be 1.0 (but it will be normalized)
     // If no mix factors are given, the old mix is preserved
     const char mixing_codes[] = { LIST_N(MIXING_STEPPERS, 'A', 'B', 'C', 'D', 'H', 'I') };
diff --git a/Marlin/src/gcode/gcode.cpp b/Marlin/src/gcode/gcode.cpp
index 4902cebde2..d519bd4e29 100644
--- a/Marlin/src/gcode/gcode.cpp
+++ b/Marlin/src/gcode/gcode.cpp
@@ -153,7 +153,7 @@ int8_t GcodeSuite::get_target_e_stepper_from_command(const int8_t dval/*=-1*/) {
 }
 
 /**
- * Set XYZ...E destination and feedrate from the current GCode command
+ * Set XYZ...E destination and feedrate from the current G-Code command
  *
  *  - Set destination from included axis codes
  *  - Set to current for missing axis codes
@@ -459,7 +459,7 @@ void GcodeSuite::process_parsed_command(const bool no_ok/*=false*/) {
       #endif
 
       #if ENABLED(DEBUG_GCODE_PARSER)
-        case 800: parser.debug(); break;                          // G800: GCode Parser Test for G
+        case 800: parser.debug(); break;                          // G800: G-Code Parser Test for G
       #endif
 
       default: parser.unknown_command_warning(); break;
@@ -1035,7 +1035,7 @@ void GcodeSuite::process_parsed_command(const bool no_ok/*=false*/) {
       #endif
 
       #if ENABLED(DEBUG_GCODE_PARSER)
-        case 800: parser.debug(); break;                          // M800: GCode Parser Test for M
+        case 800: parser.debug(); break;                          // M800: G-Code Parser Test for M
       #endif
 
       #if ENABLED(GCODE_REPEAT_MARKERS)
diff --git a/Marlin/src/gcode/gcode.h b/Marlin/src/gcode/gcode.h
index 5e6e400cf1..61ff0b047c 100644
--- a/Marlin/src/gcode/gcode.h
+++ b/Marlin/src/gcode/gcode.h
@@ -462,7 +462,7 @@ public:
      */
     enum MarlinBusyState : char {
       NOT_BUSY,           // Not in a handler
-      IN_HANDLER,         // Processing a GCode
+      IN_HANDLER,         // Processing a G-Code
       IN_PROCESS,         // Known to be blocking command input (as in G29)
       PAUSED_FOR_USER,    // Blocking pending any input
       PAUSED_FOR_INPUT    // Blocking pending text input (concept)
diff --git a/Marlin/src/gcode/parser.cpp b/Marlin/src/gcode/parser.cpp
index f2835f5891..646e362517 100644
--- a/Marlin/src/gcode/parser.cpp
+++ b/Marlin/src/gcode/parser.cpp
@@ -21,7 +21,7 @@
  */
 
 /**
- * parser.cpp - Parser for a GCode line, providing a parameter interface.
+ * parser.cpp - Parser for a G-Code line, providing a parameter interface.
  */
 
 #include "parser.h"
@@ -66,7 +66,7 @@ uint16_t GCodeParser::codenum;
   char *GCodeParser::command_args; // start of parameters
 #endif
 
-// Create a global instance of the GCode parser singleton
+// Create a global instance of the G-Code parser singleton
 GCodeParser parser;
 
 /**
@@ -108,7 +108,7 @@ void GCodeParser::reset() {
 
 /**
  * Populate the command line state (command_letter, codenum, subcode, and string_arg)
- * by parsing a single line of GCode. 58 bytes of SRAM are used to speed up seen/value.
+ * by parsing a single line of G-Code. 58 bytes of SRAM are used to speed up seen/value.
  */
 void GCodeParser::parse(char *p) {
 
@@ -317,7 +317,7 @@ void GCodeParser::parse(char *p) {
     #endif
 
     #if ENABLED(FASTER_GCODE_PARSER)
-      // Arguments MUST be uppercase for fast GCode parsing
+      // Arguments MUST be uppercase for fast G-Code parsing
       #define PARAM_OK(P) WITHIN((P), 'A', 'Z')
     #else
       #define PARAM_OK(P) true
diff --git a/Marlin/src/gcode/parser.h b/Marlin/src/gcode/parser.h
index c05d6f32c5..5d162c0a41 100644
--- a/Marlin/src/gcode/parser.h
+++ b/Marlin/src/gcode/parser.h
@@ -22,8 +22,8 @@
 #pragma once
 
 /**
- * parser.h - Parser for a GCode line, providing a parameter interface.
- *           Codes like M149 control the way the GCode parser behaves,
+ * parser.h - Parser for a G-Code line, providing a parameter interface.
+ *           Codes like M149 control the way the G-Code parser behaves,
  *           so settings for these codes are located in this class.
  */
 
@@ -43,7 +43,7 @@
 #endif
 
 /**
- * GCode parser
+ * G-Code parser
  *
  *  - Parse a single G-code line for its letter, code, subcode, and parameters
  *  - FASTER_GCODE_PARSER:
@@ -68,7 +68,7 @@ private:
 
 public:
 
-  // Global states for GCode-level units features
+  // Global states for G-Code-level units features
 
   static bool volumetric_enabled;
 
@@ -233,7 +233,7 @@ public:
     FORCE_INLINE static char* unescape_string(char* &src) { return src; }
   #endif
 
-  // Populate all fields by parsing a single line of GCode
+  // Populate all fields by parsing a single line of G-Code
   // This uses 54 bytes of SRAM to speed up seen/value
   static void parse(char * p);
 
diff --git a/Marlin/src/gcode/queue.h b/Marlin/src/gcode/queue.h
index 25b9f5cf9b..aa7ef99f47 100644
--- a/Marlin/src/gcode/queue.h
+++ b/Marlin/src/gcode/queue.h
@@ -35,7 +35,7 @@ public:
    */
   struct SerialState {
     /**
-     * GCode line number handling. Hosts may include line numbers when sending
+     * G-Code line number handling. Hosts may include line numbers when sending
      * commands to Marlin, and lines will be checked for sequentiality.
      * M110 N<int> sets the current line number.
      */
@@ -48,7 +48,7 @@ public:
   static SerialState serial_state[NUM_SERIAL]; //!< Serial states for each serial port
 
   /**
-   * GCode Command Queue
+   * G-Code Command Queue
    * A simple (circular) ring buffer of BUFSIZE command strings.
    *
    * Commands are copied into this buffer by the command injectors
diff --git a/Marlin/src/lcd/e3v2/jyersui/dwin.cpp b/Marlin/src/lcd/e3v2/jyersui/dwin.cpp
index 343252df4c..0b3c979d9e 100644
--- a/Marlin/src/lcd/e3v2/jyersui/dwin.cpp
+++ b/Marlin/src/lcd/e3v2/jyersui/dwin.cpp
@@ -4201,7 +4201,7 @@ void JyersDWIN::popupHandler(const PopupID popupid, const bool option/*=false*/)
     case Popup_PIDWait:       drawPopup(F("PID Autotune"), F("in process"), F("Please wait until done."), Proc_Wait, ICON_BLTouch); break;
     case Popup_MPCWait:       drawPopup(F("MPC Autotune"), F("in process"), F("Please wait until done."), Proc_Wait, ICON_BLTouch); break;
     case Popup_Resuming:      drawPopup(F("Resuming Print"), F("Please wait until done."), F(""), Proc_Wait, ICON_BLTouch); break;
-    case Popup_Custom:        drawPopup(F("Running Custom GCode"), F("Please wait until done."), F(""), Proc_Wait, ICON_BLTouch); break;
+    case Popup_Custom:        drawPopup(F("Running Custom G-Code"), F("Please wait until done."), F(""), Proc_Wait, ICON_BLTouch); break;
     default: break;
   }
 }
diff --git a/docs/Queue.md b/docs/Queue.md
index bce68b0551..6d4fb9d041 100644
--- a/docs/Queue.md
+++ b/docs/Queue.md
@@ -19,7 +19,7 @@ Here's a basic flowchart of Marlin command processing:
 | Host |                             |  SerialState         RingBuffer      |     |           |
 |      |             Marlin          |  NUM_SERIAL           BUF_SIZE       |     | Marlin    |
 +--+---+        R/TX_BUFFER_SIZE     |    +---+        +------------------+ |     |           |
-   |             +------------+      |    |   |        |                  | |     | GCode     |
+   |             +------------+      |    |   |        |                  | |     | G-Code    |
    |             |            |      |    |   |        |   MAX_CMD_SIZE   +-+-----> processor |
    |             | Platform   |      |    |   | On EOL | +--------------+ | r_pos |           |
    +-------------> serial's   +----------->   +--------> |   G-code     | | |     +-----------+