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ponderous

[pon-der-uhs] / ˈpɒn dər əs /
ADJECTIVE
heavy, cumbersome
Synonyms
STRONGEST
awkward bulky clumsy unwieldy weighty
WEAK
burdensome cumbrous dull elephantine graceless hefty huge laborious lifeless lumbering massive onerous oppressive substantial troublesome unhandy
Antonyms
STRONGEST
adroit clever convenient dexterous easy graceful handy small thin
WEAK
airy buoyant delicate fun light unburdensome
ADJECTIVE
dreary, tedious
Synonyms
STRONGEST
labored monotonous plodding stilted stodgy stuffy
WEAK
arid barren cardboard dry dull heavy humdrum lifeless long-winded pedantic pedestrian prolix stiff vapid verbose wooden
Antonyms
STRONGEST
exciting
WEAK
airy buoyant delicate fun light unburdensome

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