The definition of appall means to invoke feelings of offense, surprise, fear or terror.
(verb)An example of something that might appall are someone's horrible table manners at an upscale fine dining establishment.
See appall in Webster's New World College Dictionary
transitive verb
Origin: ME apallen < OFr apalir < a-, to + palir, to grow pale < L palescere < pallere, to be pale: see pale
See appall in American Heritage Dictionary 4
transitive verb ap·palled, ap·pall·ing, ap·palls
Origin:
Origin: Middle English apallen, to grow faint
Origin: , from Old French apalir
Origin: : a-, to (from Latin ad-; see ad-)
Origin: + palir, to grow pale (from pale, pale, from Latin pallidus, from pallēre, to grow pale; see pel-1 in Indo-European roots)
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