See ponderous in Webster's New World Roget's A-Z Thesaurus II
adjective
Having a relatively great weight:
heavy, heavyweight, hefty, massive, weighty. See heavyUnwieldy or clumsy, especially due to excess weight:
cumbersome, cumbrous, heavy, lumpish, lumpy. See easy, heavyLacking fluency or gracefulness:
elephantine, heavy-handed, labored. See good
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