An archaic form meaning appeasement or the act of appeasing (distinct from 'appallment').
From Old French 'apaier' meaning 'to appease,' from 'a-' + 'paix' (peace). This is etymologically distinct from 'appall' despite similar spelling.
This is a sneaky homophone situation—'appalment' and 'appallment' sound nearly identical but come from completely different root words and mean opposite things!
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