reparation vs expiation

reparation and expiation both are nouns.

Word	Noun	Adjective	Verb	Adverb
reparation	Yes	No	No	No
expiation	Yes	No	No	No

As nouns, expiation is a hypernym of reparation; that is, expiation is a word with a broader meaning than reparation:

reparation: something done or paid in expiation of a wrong
expiation: the act of atoning for sin or wrongdoing (especially appeasing a deity)

Other hypernyms of reparation include atonement, propitiation.

reparation (noun)	expiation (noun)
something done or paid in expiation of a wrong	the act of atoning for sin or wrongdoing (especially appeasing a deity)
the act of putting something in working order again	compensation for a wrong
(usually plural) compensation exacted from a defeated nation by the victors
compensation (given or received) for an insult or injury