diff --git a/htdocs/langs/en_US/main.lang b/htdocs/langs/en_US/main.lang
index bb8ffeb6b4f..150abc1b4b8 100644
--- a/htdocs/langs/en_US/main.lang
+++ b/htdocs/langs/en_US/main.lang
@@ -256,6 +256,7 @@ DurationDays=days
 Year=Year
 Month=Month
 Week=Week
+WeekShort=Week
 Day=Day
 Hour=Hour
 Minute=Minute
diff --git a/htdocs/projet/activity/perweek.php b/htdocs/projet/activity/perweek.php
index 53b9ba151b4..4a4a0a27713 100644
--- a/htdocs/projet/activity/perweek.php
+++ b/htdocs/projet/activity/perweek.php
@@ -291,7 +291,7 @@ $param=($mode?'&mode='.$mode:'');
 
 // Show navigation bar
 $nav ="<a href=\"?year=".$prev_year."&amp;month=".$prev_month."&amp;day=".$prev_day.$param."\">".img_previous($langs->trans("Previous"))."</a>\n";
-$nav.=" <span id=\"month_name\">".dol_print_date(dol_mktime(0,0,0,$first_month,$first_day,$first_year),"%Y").", ".$langs->trans("Week")." ".$week." </span>\n";
+$nav.=" <span id=\"month_name\">".dol_print_date(dol_mktime(0,0,0,$first_month,$first_day,$first_year),"%Y").", ".$langs->trans("WeekShort")." ".$week." </span>\n";
 $nav.="<a href=\"?year=".$next_year."&amp;month=".$next_month."&amp;day=".$next_day.$param."\">".img_next($langs->trans("Next"))."</a>\n";
 $nav.=" &nbsp; (<a href=\"?year=".$nowyear."&amp;month=".$nowmonth."&amp;day=".$nowday.$param."\">".$langs->trans("Today")."</a>)";
 $nav.='<br>'.$form->select_date(-1,'',0,0,2,"addtime",1,0,1).' ';