ex·pi·ate 
(ĕkspē-āt′)
(ĕkspē-āt′)v. ex·pi·at·ed, ex·pi·at·ing, ex·pi·ates
v.tr.
To make amends or reparation for; atone for: expiate one's sins by acts of penance.
v.intr.
To make amends; atone.
[Latin expiāre, expiāt- : ex-, intensive pref.; see EX- + piāre, to atone (from pius, devout).]
expi·a′tor n.