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acro-

American  
  1. a combining form with the meanings “height,” “tip end,” “extremities of the body,” used in the formation of compound words.

    acrophobia.


acro- British  

combining form

  1. denoting something at a height, summit, top, tip, beginning, or end

    acropolis

    acrogen

  2. denoting an extremity of the human body

    acromegaly

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of acro-

< Greek, combining form of ákros topmost, highest; akin to Latin ācer sharp. acme, ear 2