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fissi-

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

    fissiparous.


fissi- British  

combining form

  1. indicating a splitting or cleft

    fissirostral

"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 fissi-

< Latin, combining form of fissus cloven, fissum fissure, special uses of past participle of findere to split