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-ard

a suffix forming nouns that denote persons who regularly engage in an activity, or who are characterized in a certain way, as indicated by the stem; now usually pejorative: coward; dullard; drunkard; wizard.
Also -art.

Origin of -ard

Middle English < Old French, probably extracted from Frankish compound personal names; compare Old High German Adalhart (French Alard), Bernhart (French Bernard), with 2nd element -hart literally, strong, hardy, hard (cognate with Old English -heard in names), often merely as intensifier of quality denoted in 1st element.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for -ard

-ard

-art

suffix forming nouns

indicating a person who does something, esp to excess, or is characterized by a certain qualitybraggart; drunkard; dullard

Word Origin for -ard

via Old French from Germanic -hard (literally: hardy, bold), the final element in many Germanic masculine names, such as Bernhard Bernard, Gerhart Gerard, etc
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
Word Origin and History for -ard

also -art, from Old French -ard, -art, from German -hard, -hart "hardy," forming the second element in many personal names, often used as an intensifier, but in Middle High German and Dutch used as a pejorative element in common nouns, and thus passing into Middle English in bastard, coward, blaffard ("one who stammers"), etc. It thus became a living element in English, e.g. buzzard, drunkard.

Online Etymology Dictionary, © 2010 Douglas Harper