diff --git a/lisp/org-agenda.el b/lisp/org-agenda.el
index 8d5655f9a..ad4018d6e 100644
--- a/lisp/org-agenda.el
+++ b/lisp/org-agenda.el
@@ -52,7 +52,7 @@
 
 (declare-function diary-add-to-list "diary-lib"
                   (date string specifier &optional marker globcolor literal))
-(declare-function calendar-absolute-from-iso    "cal-iso"    (date))
+(declare-function calendar-iso-to-absolute      "cal-iso"    (date))
 (declare-function calendar-astro-date-string    "cal-julian" (&optional date))
 (declare-function calendar-bahai-date-string    "cal-bahai"  (&optional date))
 (declare-function calendar-chinese-date-string  "cal-china"  (&optional date))
@@ -8023,7 +8023,7 @@ so that the date SD will be in that range."
 	    (setq y1 (org-small-year-to-year (/ n 100))
 		  n (mod n 100)))
 	  (setq sd
-		(calendar-absolute-from-iso
+		(calendar-iso-to-absolute
 		 (list n 1
 		       (or y1 (nth 2 (calendar-iso-from-absolute sd)))))))))
      ((eq span 'month)
diff --git a/lisp/org-clock.el b/lisp/org-clock.el
index 88243dbc7..c772dd988 100644
--- a/lisp/org-clock.el
+++ b/lisp/org-clock.el
@@ -32,7 +32,7 @@
   (require 'cl))
 (require 'org)
 
-(declare-function calendar-absolute-from-iso "cal-iso" (&optional date))
+(declare-function calendar-iso-to-absolute "cal-iso" (&optional date))
 (declare-function notifications-notify "notifications" (&rest params))
 (declare-function org-pop-to-buffer-same-window "org-compat" (&optional buffer-or-name norecord label))
 (declare-function org-element-property "org-element" (property element))
@@ -2127,7 +2127,7 @@ If you can combine both, the month starting day will have priority."
       (setq y (string-to-number (match-string 1 skey))
 	    w (string-to-number (match-string 2 skey)))
       (setq date (calendar-gregorian-from-absolute
-		  (calendar-absolute-from-iso (list w 1 y))))
+		  (calendar-iso-to-absolute (list w 1 y))))
       (setq d (nth 1 date) month (car date) y (nth 2 date)
 	    dow 1
 	    key 'week))
@@ -2136,7 +2136,7 @@ If you can combine both, the month starting day will have priority."
       (setq y (string-to-number (match-string 1 skey)))
       (setq q (string-to-number (match-string 2 skey)))
       (setq date (calendar-gregorian-from-absolute
-		  (calendar-absolute-from-iso (org-quarter-to-date q y))))
+		  (calendar-iso-to-absolute (org-quarter-to-date q y))))
       (setq d (nth 1 date) month (car date) y (nth 2 date)
             dow 1
             key 'quarter))
@@ -2271,7 +2271,7 @@ the currently selected interval size."
 	   ((and wp (string-match "w\\|W" wp) mw (> (length wp) 0))
 	    (require 'cal-iso)
 	    (setq date (calendar-gregorian-from-absolute
-			(calendar-absolute-from-iso (list (+ mw n) 1 y))))
+			(calendar-iso-to-absolute (list (+ mw n) 1 y))))
 	    (setq ins (format-time-string
 		       "%G-W%V"
 		       (encode-time 0 0 0 (nth 1 date) (car date) (nth 2 date)))))
@@ -2288,7 +2288,7 @@ the currently selected interval size."
 		      y (- y 1))
 	      ())
 	    (setq date (calendar-gregorian-from-absolute
-			(calendar-absolute-from-iso (org-quarter-to-date (+ mw n) y))))
+			(calendar-iso-to-absolute (org-quarter-to-date (+ mw n) y))))
 	    (setq ins (format-time-string
 		       (concat (number-to-string y) "-Q" (number-to-string (+ mw n)))
 		       (encode-time 0 0 0 (nth 1 date) (car date) (nth 2 date)))))
diff --git a/lisp/org.el b/lisp/org.el
index fb2458f44..2894c5adc 100755
--- a/lisp/org.el
+++ b/lisp/org.el
@@ -4443,7 +4443,7 @@ Normal means, no org-mode-specific context."
 (defvar mark-active)
 
 ;; Various packages
-(declare-function calendar-absolute-from-iso    "cal-iso"    (date))
+(declare-function calendar-iso-to-absolute    "cal-iso"    (date))
 (declare-function calendar-forward-day          "cal-move"   (arg))
 (declare-function calendar-goto-date            "cal-move"   (date))
 (declare-function calendar-goto-today           "cal-move"   ())
@@ -16993,7 +16993,7 @@ user."
 	    day (or iso-weekday wday 1)
 	    wday nil ; to make sure that the trigger below does not match
 	    iso-date (calendar-gregorian-from-absolute
-		      (calendar-absolute-from-iso
+		      (calendar-iso-to-absolute
 		       (list iso-week day year))))
 					; FIXME:  Should we also push ISO weeks into the future?
 					;      (when (and org-read-date-prefer-future
@@ -17002,7 +17002,7 @@ user."
 					;		    (time-to-days (current-time))))
 					;	(setq year (1+ year)
 					;	      iso-date (calendar-gregorian-from-absolute
-					;			(calendar-absolute-from-iso
+					;			(calendar-iso-to-absolute
 					;			 (list iso-week day year)))))
       (setq month (car iso-date)
 	    year (nth 2 iso-date)