Adjective underhand has 2 senses
- underhand, underhanded, underarm - with hand brought forward and up from below shoulder level; "an underhand pitch"; "an underhand stroke"
Antonyms: overhand, overhanded, overarm, round-arm
- sneaky, underhand, underhanded - marked by deception; "achieved success in business only by underhand methods"
Antonym: straight (indirect, via crooked)
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Adverbial underhand has 2 senses
- underhandedly, underhand - slyly and secretly; "Mean revenge, committed underhand"- John Donne; "oldline aristocratic diplomats underhandedly undermined the attempt...to align Germany with the Western democracies"- C.G.Bowers
- underarm, underhand - with the hand swung below shoulder level'; "throwing a ball underarm"
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