Noun
dalradian (plural dalradians)
(geology) A series of metamorphic rocks that are difficult to assign a position in the local stratigraphical sequence
Dalradian (plural Dalradians)
Alternative form of dalradian
The name of the kingdom survives in the terminology of the Dalradian geological series, a term coined by Archibald Geikie in 1891 because its outcrop has a similar geographical reach to that of the former Dál Riata. Source: Internet