gorillagram
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gorillagram
(ɡəˈrɪləˌɡræm)n
informal a jocular greetings message delivered to someone celebrating a birthday, engagement, etc, by a person dressed as a gorilla
[C20: from gorilla + (tele)gram]
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014