diff --git a/etc/DEBUG b/etc/DEBUG
index 44f19900c64..dc1601a34f8 100644
--- a/etc/DEBUG
+++ b/etc/DEBUG
@@ -211,16 +211,19 @@ the debugger, but before running it, is the most efficient way of
 making sure control will be returned to the debugger when you need
 that.
 
-There is a default function to give control to the debugger.  It is
-called debugger-trap.  This is a do-nothing primitive, as a convenient
-point to return control to the debugger.  You can invoke interactively
-with "M-x debugger-trap RET".  The src/.gdbinit file in the Emacs source
-distribution sets a breakpoint on this function.
+The function 'debugger-trap' is a do-nothing interactive command that
+exists to give control to the debugger.  It is convenient to set a
+breakpoint there to give control to the debugger when the function is
+called.  You can invoke it interactively with "M-x debugger-trap RET".
+The src/.gdbinit file in the Emacs source distribution sets a breakpoint
+in this function, so if you arrange for .gdbinit to be loaded, or load
+it manually in a debugging session, the breakpoint is set for you
+automatically.
 
-'Fsignal' is a very useful place to put a breakpoint in.  All Lisp
+'Fsignal' is another very useful place to put a breakpoint in.  All Lisp
 errors go through there.  If you are only interested in errors that
-would fire the Lisp debugger, breaking at 'maybe_call_debugger' is
-useful.
+would fire the Lisp debugger, breaking at 'maybe_call_debugger' is a
+useful alternative.
 
 It is also useful to have a guaranteed way to return to the debugger
 at any arbitrary time.  When using X, this is easy: type C-z at the
diff --git a/src/eval.c b/src/eval.c
index 829d6104618..0d4ae91136e 100644
--- a/src/eval.c
+++ b/src/eval.c
@@ -3092,14 +3092,14 @@ FUNCTIONP (Lisp_Object object)
 }
 
 DEFUN ("debugger-trap", Fdebugger_trap, Sdebugger_trap, 0, 0, "",
-       doc: /* Trap execution flow and hand over control to GDB.
-The Emacs source file src/.gdbinit uses this via the GDB command
-"break Fdebugger_trap".
+       doc: /* Stop Emacs and hand over control to GDB.
+The Emacs source file src/.gdbinit sets a breakpoint in this function.
 
-This function has no effect.  It is reserved for debugging, and is not
-called by Emacs otherwise.
+This function does nothing.  It is not called by Emacs otherwise, and
+exists so that calling it or invoking it interactively will cause
+GDB to kick in.
 
-For Lisp debugging see debug, as well as edebug, in the manual:
+For Lisp debugging see `debug', as well as `edebug', in the manual:
 "(elisp) Debugging".  */)
   (void)
 {