This work looks at basic colour terms in Modern Irish by presenting the historical development of these terms since their earliest attestation and in comparison with the other Gaelic languages, namely, Scottish Gaelic and Manx. These terms are analysed based on lexicographical and didactic material, as well as their use in placenames and proverbs, resources with great potential but which have been underused in colour terminology research in general. Its conclusion is the presentation of fieldwork results with native speakers from all major Irish dialects based on their responses to the colours of items in pictures, research which has never been previously conducted, to see whether their use of colour terminology matches that as presented, and to comment on the current state of Irish basic colour terminology.