From Old Irish leth (“side”), from Proto-Celtic *letos, perhaps cognate with Latin latus (“side”), or from Proto-Celtic *ɸletos.
Celtic cognates include Welsh lled (“breadth, width, half”), Middle Breton let, led (“large”), and Cornish les.
leath f (genitive singular leithe, nominative plural leatha)
- side; part, direction
- half; part, portion
Is fearr leath ná meath. ― Something is better than nothing.
Terms derived from leath
- i leith (“hither; aside, apart; thenceforth”, adverb)
- i leith (“in the direction of; tending towards; on the side of, in favour of; on behalf of, for the sake of; resorting to, trusting in, dependent on”)
- i leith is go (“as if”)
- i leith le (“in regard to”)
- in áit ar leith, in áit faoi leith, in a place apart
- leath- (“lying, turned, to one side; lopsided, tilted; one-sided, partial; half-, hemi-, semi-; half-grown; one of two, of a pair”)
- leath aife (“half-ebb”)
leath (present analytic leathann, future analytic leathfaidh, verbal noun leathadh, past participle leata) (transitive, intransitive)
- disperse, spread, cover
- open wide, expand
- become confused, indistinct
- (literary) halve, divide, split (in half); diminish
First Conjugation (A)
* Indirect relative
† Archaic or dialect form
- ^ Matasović, Ranko (2009), “*letos”, in Etymological Dictionary of Proto-Celtic (Leiden Indo-European Etymological Dictionary Series; 9), Leiden: Brill, ISBN 978-90-04-17336-1, pages 238-239
- “leth” in Dictionary of the Irish Language, Royal Irish Academy, 1913–76.
- “leaṫ” in Foclóir Gaeḋilge agus Béarla, Irish Texts Society, 2nd ed., 1927, by Patrick S. Dinneen.
- "leath" in Foclóir Gaeilge-Béarla, An Gúm, 1977, by Niall Ó Dónaill.