The definition of tough is someone or something strong and flexible, rugged, harsh or hard to chew or cut through.(adjective)
See tough in Webster's New World College Dictionary
Origin: ME < OE toh, akin to Ger zäh, tough, viscous, prob. < IE base *denk-, to bite > tongs
See tough in American Heritage Dictionary 4
adjective tough·er, tough·est
Origin: Middle English
Origin: , from Old English tōh.
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