Word forms: hair shirts
1. countable noun A hair shirt is a shirt made of rough uncomfortable cloth which some religious people used to wear to punish themselves. ⇒ He was sent barefoot wearing only a hair shirt into the wilderness as a penance. 2. countable noun If you say that someone is wearing a hair shirt, you mean that they are trying to punish themselves to show they are sorry for something they have done. ⇒ No one is asking you to put on a hair shirt and give up all your luxuries.
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