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definitions

gorillagram

noun
  1. informal a jocular greetings message delivered to someone celebrating a birthday, engagement, etc, by a person dressed as a gorilla

Word Origin for gorillagram

C20: from gorilla + (tele) gram
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