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Definitions

offhand

[awf-hand, of-] / ˈɔfˈhænd, ˈɒf- /
ADJECTIVE
abrupt, careless
Synonyms
STRONGEST
casual curt easygoing folksy glib perfunctory
WEAK
aloof breezy brusque cavalier cool informal laid-back mellow unceremonious unconcerned uninterested
Antonyms
WEAK
calculated careful considered deliberate planned practiced
ADJECTIVE
ad-lib, extemporaneous
Synonyms
STRONGEST
impromptu spontaneous
WEAK
by-the-way extemporary extempore improvised informal off the cuff off the hip off the top of head spur-of-the-moment throwaway unpremeditated unprepared unrehearsed unstudied without preparation
Antonyms
WEAK
calculated careful considered deliberate planned practiced

From Roget's 21st Century Thesaurus, Third Edition Copyright © 2013 by the Philip Lief Group.