diff --git a/lisp/term/x-win.el b/lisp/term/x-win.el
index 56061371fe..d4681e3e9f 100644
--- a/lisp/term/x-win.el
+++ b/lisp/term/x-win.el
@@ -302,7 +302,11 @@ as returned by `x-server-vendor'."
     (setq i (1+ i))))
 
 ;; Table from Kuhn's proposed additions to the `KEYSYM Encoding'
-;; appendix to the X protocol definition.
+;; appendix to the X protocol definition. As indicated, some of these
+;; have been corrected using information found in keysymdef.h which
+;; on a typical system is installed at /usr/include/X11/keysymdef.h. The
+;; version used here is from xorgproto version 2019.1 found here:
+;; https://gitlab.freedesktop.org/xorg/proto/xorgproto/blob/e0bba743ae7c549c58f92677b239ec7878548228/include/X11/keysymdef.h
 (dolist
      (pair
       '(
@@ -579,6 +583,7 @@ as returned by `x-server-vendor'."
 	(#x6aa . ?њ)
 	(#x6ab . ?ћ)
 	(#x6ac . ?ќ)
+	(#x6ad . ?ґ) ;; Source: keysymdef.h
 	(#x6ae . ?ў)
 	(#x6af . ?џ)
 	(#x6b0 . ?№)
@@ -594,6 +599,7 @@ as returned by `x-server-vendor'."
 	(#x6ba . ?Њ)
 	(#x6bb . ?Ћ)
 	(#x6bc . ?Ќ)
+	(#x6bd . ?Ґ) ;; Source: keysymdef.h
 	(#x6be . ?Ў)
 	(#x6bf . ?Џ)
 	(#x6c0 . ?ю)
@@ -810,6 +816,7 @@ as returned by `x-server-vendor'."
 	(#xaa8 . ? )
 	(#xaa9 . ?—)
 	(#xaaa . ?–)
+	(#xaac . ?␣) ;; Source: keysymdef.h
 	(#xaae . ?…)
 	(#xaaf . ?‥)
 	(#xab0 . ?⅓)
@@ -822,7 +829,17 @@ as returned by `x-server-vendor'."
 	(#xab7 . ?⅚)
 	(#xab8 . ?℅)
 	(#xabb . ?‒)
+	;; In keysymdef.h, the keysyms 0xabc and 0xabe are listed as
+	;; U+27E8 and U+27E9 respectively. However, the parentheses
+	;; indicate that these mappings are deprecated legacy keysyms
+	;; that are either not one-to-one or semantically unclear. In
+	;; order to not introduce any incompatibility with possible
+	;; existing workflows that expect these keysyms to map as they
+	;; currently do, to 0x2329 and 0x232a, respectively, they are
+	;; left as they are. In particular, PuTTY is known to agree with
+	;; this mapping.
 	(#xabc . ?〈)
+	(#xabd . ?.) ;; Source: keysymdef.h
 	(#xabe . ?〉)
 	(#xac3 . ?⅛)
 	(#xac4 . ?⅜)
@@ -839,6 +856,7 @@ as returned by `x-server-vendor'."
 	(#xad2 . ?“)
 	(#xad3 . ?”)
 	(#xad4 . ?℞)
+	(#xad5 . ?‰) ;; Source: keysymdef.h
 	(#xad6 . ?′)
 	(#xad7 . ?″)
 	(#xad9 . ?✝)
@@ -883,20 +901,29 @@ as returned by `x-server-vendor'."
 	(#xba8 . ?∨)
 	(#xba9 . ?∧)
 	(#xbc0 . ?¯)
-	(#xbc2 . ?⊥)
+	;; Source for #xbc2: keysymdef.h. Note that the
+	;; `KEYSYM Encoding' appendix to the X protocol definition is
+	;; incorrect.
+	(#xbc2 . ?⊤)
 	(#xbc3 . ?∩)
 	(#xbc4 . ?⌊)
 	(#xbc6 . ?_)
 	(#xbca . ?∘)
 	(#xbcc . ?⎕)
-	(#xbce . ?⊤)
+	;; Source for #xbce: keysymdef.h. Note that the
+	;; `KEYSYM Encoding' appendix to the X protocol definition is
+	;; incorrect.
+	(#xbce . ?⊥)
 	(#xbcf . ?○)
 	(#xbd3 . ?⌈)
 	(#xbd6 . ?∪)
 	(#xbd8 . ?⊃)
 	(#xbda . ?⊂)
-	(#xbdc . ?⊢)
-	(#xbfc . ?⊣)
+	;; Source for #xbdc and #xbfc: keysymdef.h. Note that the
+	;; `KEYSYM Encoding' appendix to the X protocol definition is
+	;; incorrect.
+	(#xbdc . ?⊣)
+	(#xbfc . ?⊢)
 	;; Hebrew
 	(#xcdf . ?‗)
 	(#xce0 . ?א)
@@ -1143,6 +1170,9 @@ as returned by `x-server-vendor'."
 ;; #x0aff	CURSOR	Publish
 ;; #x0dde	THAI MAIHANAKAT	Thai
 
+;; However, keysymdef.h does have mappings for #x0aac and #x0abd, which
+;; are used above.
+
 
 ;;;; Selections