1 [uncountable and countable]RR
an action that is against religious rules and is considered to be an offence against God
the sin of pride
She needed to confess her sins and ask for forgiveness.
He knew that he had committed a terrible sin.
the seven deadly sins (=seven bad feelings or desires, in the Christian religion)
something that you think is very wrong
it is a sin (to do something)
There's so much lovely food here, it would be a sin to waste it.
if two people live in sin, they live together in a sexual relationship without being married
4 especially British English spoken
very unhappy, ugly, or guilty:
I saw Margaret this morning looking as miserable as sin.
5 especially British English spokenXX
an expression used to suggest jokingly that you have to do something as a punishment:
I work at head office now, for my sins.