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Synonyms for Underhand (same or very similar meaning)

WordNet sense 1 (with hand brought forward and up from below shoulder level):
underarm, underhanded

WordNet sense 2 (marked by deception):

WordNet sense 3 (not straight; dishonest or immoral or evasive):
corrupt, crooked, crooked

WordNet sense 4 (slyly and secretly):

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