The story
- Latin · derived fromexpīrātiōnem
- Middle English · inherited fromexpiracioun
- English todayexpiration
From Middle English expiracioun, exspiracioun (“vapor, breath”), from Latin expīrātiōnem, exspīrātiōnem, accusative singular of expīrātiō, exspīrātiō. By surface analysis, expire + -ation.
Etymology from Wiktionary, CC BY-SA 4.0.