- Sin can also be an abbreviation of sine in Mathematics.
- SIN can also be the abbreviation of Singapore.
A sin an act that violates God's will, especially in Abrahamic religions. It may be something that most religion tells its believers is a bad thing to do, usually because the thing is believed to draw people away from God and true happiness.
Religions usually say that God told them that some things are sins through prophets (messengers from God). In Christianity and Judaism Moses was given the Ten Commandments by God. (see Exodus 20) Usually the sacred books of a religion talk about sins. There are some things that most religions agree are sins. For example, many religions agree that it is wrong to kill people (murder).
There are other things that are sins in only a few religions. For example, Muslims and Jews say that it is wrong to eat pork, and Hindus do not eat beef, but other religions do not think that it's wrong to eat these things. But see also vegetarianism.
Most religions describe sins as actions that break their rules.