n. & v.
n. 1 an act of self-punishment as reparation for guilt. 2 a (in the RC and Orthodox Church) a sacrament including confession of and absolution for a sin. b a penalty imposed esp. by a priest, or undertaken voluntarily, for a sin.
v.tr. impose a penance on. do penance perform a penance.
[ ME f. OF f. L paenitentia (as PENITENT) ]