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word-forming element meaning "highest, topmost, at the extremities," before vowels, acr-, from Greek akro- "pertaining to an end, extreme," comb. form of akros "at the end, at the top" (see acrid).
acro- or acr-pref.
Top; summit; height: acrophobia.
Tip; beginning: acrosome.
Extremity of the body: acroparalysis.