Where does “defunct” come from?

defunct (Old French) comes from Latin defunctus, from Latin defungor, from Latin dē-, from Latin dē, from Latin post, from Latin poste, from Proto-Italic posti, from Proto-Indo-European pósti — afterwards, post; by, at.

Ancestry of “defunct”, step by step

StepLanguageWordMeaning
1Latindefunctusdone with, performed, finished, having finished;...
2LatindefungorI have done with, perform, finish, carry out; I...
3Latindē-of; from
4Latinof; concerning; about
5Latinpostbehind; after, since, besides, except; behind,...
6Latinposteablative singular of postis
7Proto-Italicpostibehind, after
8Proto-Indo-Europeanpóstiafter
9Proto-Indo-Europeanpósafterwards, post; by, at
Every word from Proto-Indo-European pósEvery word from Latin dē-Every word from Proto-Indo-European pósti