To overcome is to prevail in spite of adversity, to successfully solve a problem or defeat an opponent, or to be consumed with something.
To defeat is defined as to beat someone at something or to prevent something from happening.
To cause someone to become quiet.
Find another word for shout-down. In this page you can discover 5 synonyms, antonyms, idiomatic expressions, and related words for shout-down, like: silence, shut up, overcome, defeat and quiet.