Meanings
ac-1
- oak.
Acton
ac-2
ac-3
- On.
ac- + knowledge → acknowledge
Origin
ac- · prefix
- Old Englishāc“oak”
- Englishac-
From Old English āc (“oak”) (but not part of the etymology of acorn).
More words from Old English
Full word history & related roots →ac- · prefix
- Latinad-“to, toward”
- Old Frencha-
- Middle Englisha-
- Englishac-
Assimilated form of ad- before c, k, q. Around 1500 the c was added to some versions of the a- prefix. From Middle English a-, from Old French a-, from Latin ad- (“to, toward”).
More words from Middle English, Old French, Latin
Full word history & related roots →ac- · prefix
- Old Englishge-
- Englishac-
Assimilated form of a-. Around 1500 the c was added to some versions of the a- prefix. From a- (“on”), from Old English ge-.
More words from Old English
Full word history & related roots →Cite this entry
ac-. (n.d.). In WatkinsX Dictionary. Retrieved November 2, 2026, from https://dictionary.watkinsx.com/word/ac-
“ac-.” WatkinsX Dictionary, https://dictionary.watkinsx.com/word/ac-. Accessed November 2, 2026.
WatkinsX Dictionary, s.v. “ac-,” accessed November 2, 2026, https://dictionary.watkinsx.com/word/ac-.
Source: ac- on Wiktionary, CC BY-SA 4.0.