noun
Big Ben
Refers to the famous clock tower in London.
ロンドンに行ったら、ビッグベンを見たい。
When I go to London, I want to see Big Ben.
noun
Jocular, vulgar pun on 大便 (daiben, 'feces'); used humorously.
See also: 大便
「ビッグベンが出そう」なんて、下品な冗談だよ。
Saying 'I feel a Big Ben coming' is a crude joke.
Sense 1 is a direct loan from English 'Big Ben'. Sense 2 is a Japanese pun on 大便 (daiben, 'feces'), playing on the phonetic similarity.