slow to learn or understand; lacking intellectual acuity; "so dense he never understands anything I say to him"; "never met anyone quite so dim"; "although dull at classical learning, at mathematics he was uncommonly quick"- Thackeray; "dumb officials make some really dumb decisions"; "he was either normally stupid or being deliberately obtuse"; "worked with the slow students"
having high relative density or specific gravity; "dense as lead"
hard to pass through because of dense growth; "dense vegetation"; "thick woods"
permitting little if any light to pass through because of denseness of matter; "dense smoke"; "heavy fog"; "impenetrable gloom"
a quantifier that can be used with count nouns and is often preceded by `as' or `too' or `so' or `that'; amounting to a large but indefinite number; "many temptations"; "the temptations are many"; "a good many"; "a great many"; "many directions"; "take as many apples as you like"; "too many clouds to see"; "never saw so many people"