acid (English)
Where does "acid" come from?
The English word 'acid' arrives via the French 'acide'[1][2]. This French term stems from the Latin 'acidus', meaning 'sour' or 'acid'[1][2][3]. The root of this Latin adjective is the verb 'aceo', which translates to 'I am sour'[1][5]. This Latin verb is derived from the Proto-Indo-European *h₂éḱ-eh₁ye-ti, an stative form built from the root *h₂eḱ- meaning 'sharp'[5]. Consequently, the word retains a connection to its original sense of sharpness that evolved through centuries of linguistic development[5].
Open questions
- The derivation of the suffix 'idus' from an Etruscan verb is a proposal attributed to Macrobius and remains a debated etymological origin. [4]
Full etymology tree
- acid (English), 'A sour substance.'
- borrowed acide (French), 'acid, acidic, sour, tart'
- borrowed acidus (Latin), 'sour, tart, acid, bitter'
- derived aceo (Latin), 'to be sour'
- inherited *h₂éḱ-eh₁ye-ti (Proto-Indo-European)
- derived *h₂eḱ- (Proto-Indo-European), 'sharp'
- inherited *h₂éḱ-eh₁ye-ti (Proto-Indo-European)
- suffix -idus (Latin), 'tending to'
- derived aceo (Latin), 'to be sour'
- borrowed acidus (Latin), 'sour, tart, acid, bitter'
- borrowed acide (French), 'acid, acidic, sour, tart'
Ancestors
- *h₂eḱ- (Proto-Indo-European)
- acide (French)
- acidus (Latin)
Cognates and doublets
- acetic (English)
- agita (English)
Descendants and derived words
- 1 (English)
- 1 (English)
- 10-undecenoic acid (English)
- 2-methyl-2-propenoic acid (English)
- aberic acid (English)
- abietic acid (English)
- abietinic acid (English)
- abscisic acid (English)
- acacic acid (English)
- acanthoic acid (English)
- aceburic acid (English)
- aceconitic acid (English)
Sources
- acid (English) - Wiktionary
- acide (French) - Wiktionary
- acidus (Latin) - Wiktionary
- idus (Latin) - Wiktionary
- aceo (Latin) - Wiktionary
Updated August 2026
Etymology data from Wiktionary, CC BY-SA 4.0 · About Miraris