modified
Weighty
Viscous
Burdensome
Dull
Gloomy
Difficult
Soggy
heavy implies relatively great density, quantity, intensity, etc. and figuratively connotes a pressing down on the mind, spirits, or senses heavy water, heavy-hearted; weighty suggests heaviness as an absolute rather than a relative quality and figuratively connotes great importance or influence a weighty problem: ponderous applies to something that is very heavy because of size or bulk and figuratively connotes a labored or dull quality a ponderous dissertation; massive stresses largeness and solidity rather than heaviness and connotes an impressiveness due to great size massive structures; cumbersome implies a heaviness and bulkiness that makes for awkward handling and, in extended use, connotes unwieldiness cumbersome formalities
See heavy in American Heritage Dictionary 4 Synonyms
See heavy in Webster's New World Roget's A-Z Thesaurus II
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