Laugh is defined as to express amusement with vocal sounds and facial movements.(verb)
An example of laugh is someone making sounds to show they think something is funny.
See laugh in Webster's New World College Dictionary
Origin: ME laughen < OE hleahhan, akin to Ger lachen (OHG hlahhan) < IE base *klēg-, to cry out, sound > Gr klangē, L clangor
See laugh in American Heritage Dictionary 4
verb laughed, laugh·ing, laughs verb, intransitive
Origin: Middle English laughen
Origin: , from Old English hlǽhhan
Origin: , probably ultimately of imitative origin.
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