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naissant

British  
/ ˈneɪsənt /

adjective

  1. heraldry (of a beast) having only the forepart shown above a horizontal division of a shield

"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 naissant

C16: from Old French, literally: being born. See nascent