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alti-

American  
  1. a combining form with the meaning “high,” used in the formation of compound words.

    altigram, altitude.


alti- British  

combining form

  1. indicating height or altitude

    altimeter

"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 alti-

Middle English < Latin alti- combining form of altus high