expiation
From LSJ
subs.
P. and V. καθαρμός, ὁ, λύσις, ἡ. Compensation: P. and V. τίσις, ἡ (Plat.), V. ποινή, ἡ, or pl. (rare P.), ἄποινα, τά (Plat. but rare P.). I am ready to die as an expiation for my country: V. θνήσκειν ἑτοῖμος πατρίδος ἐκλυτήριον (Eur., Phoen. 969).