Spanish word postre comes from Latin post, and later Latin posterior (Next, following. Posterior, more to the back.)
post (Latin)
(of space) behind, back, backwards. (of time) afterwards, after (with accusative) (of space) behind. (with accusative) (of time) after, since, (transf.) besides, except.
posterior (Latin)
Next, following. Posterior, more to the back.
postre (Spanish)
Dessert; sweet.
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