1. like sin - Adverb
2. like sin - Phrase
(informal) with great speed or effort or intensity; used for emphasis
Source: WordNetKnowledge is not like sin. There is no mystical escape from it. Leigh Brackett
drove like crazy Source: Internet
worked like hell to get the job done Source: Internet
this sprain hurts like hell Source: Internet
ran like sin for the storm cellar Source: Internet
work like thunder Source: Internet