Origin: 1350–1400; ME (< OF) < LL
apprehēnsiōn- (s. of
apprehēnsiō), equiv. to
apprehens- (
see apprehensible ) +
-iōn- -ion 
Synonyms:
1. alarm, worry, uneasiness; suspicion. Apprehension, anxiety, misgiving imply an unsettled and uneasy state of mind. Apprehension is an active state of fear, usually of some danger or misfortune: apprehension before opening a telegram. Anxiety is a somewhat prolonged state of apprehensive worry: anxiety because of a reduced income. Misgiving implies a dubious uncertainty or suspicion, as well as uneasiness: to have misgivings about the investment. 5. capture.
Antonyms:
1. composure, tranquillity. 5. release.