The story
- Proto-Indo-European*h₂éd
- Proto-Italic*ad
- Proto-Italic*ad-
- Latinad-
- Proto-Italic*kaussā
- Old Latincaussa
- Latincausa
- Latinaccūsō
- Ancient Greekαἰτῐᾱτῐκή (aitĭātĭkḗ)
- Latinaccūsātīvus
- Anglo-Normanaccusatif
- Latinaccūsātīvus
- Middle Frenchacusatif
- Latinaccūsātīvus
- Middle Englishaccusative
- Englishaccusative
- English todayaccusativity
From accusative + -ity.
Etymology from Wiktionary, CC BY-SA 4.0.