inhibit
verb
prohibit, forbid, or prevent from doing something
“Contact between the young was inhibited by strict social customs”
limit, block, or decrease the action or function of
“inhibit the action of the enzyme”
“inhibit the rate of a chemical reaction”
consciously restrain from showing; of emotions, desires, impulses, or behavior
“suppress a smile”
“he let his anger bottle up until he exploded”
make (someone) self-conscious and as a result unable to act naturally
“his father's cold and distant demeanor inhibited him emotionally”
Source: WordNet 3.1, Princeton University