idir (plus nominative, triggers no mutation, triggers lenition in the meaning ‘both (...and ...)’)
- idir fir agus mná ― between men and women
- both (paired with agus (“and”))
- idir fhir agus mhná ― both men and women
In modern usage, this preposition has inflected forms only in the plural. Idir is used with nouns and with singular pronouns in combination with another noun or pronoun:
- idir é agus mé ― between him and me
In the meaning ‘between’, this preposition does not trigger any initial mutation. In the meaning ‘both (... and ...)’ it triggers lenition of both the word following it and the word following agus.
From Old Irish etir.
- at all
- Chan 'eil idir. ― Not at all.
- Cha'n e idir. ― That is not it at all.
- Cha tig e idir. ― He will not come at all.
- No idir air a bhruicheadh. ― Nor even boiled.
- Cha'n 'eil e gu math idir. ― He is not at all well.
- Cha deanainn idir e. ― I would not do it on any account.
- Faclair Gàidhlig Dwelly Air Loidhne, Dwelly, Edward (1911), Faclair Gàidhlig gu Beurla le Dealbhan/The Illustrated [Scottish] Gaelic-English Dictionary (10th ed.), Edinburgh: Birlinn Limited, ISBN 0 901771 92 9
- A Pronouncing and Etymological Dictionary of the Gaelic Language (John Grant, Edinburgh, 1925, Compiled by Malcolm MacLennan)