Originally a variant of Helen, although now no longer associated with that name. Initial H- tended to be added and dropped rather capriciously, leading to many doublets (compare for example Esther and Hester). It is also sometimes used as a short form of Eleanor, to which, however, it is unrelated.
Scottish: habitational name from a place near Lennoxtown, north of Glasgow, which is first recorded in 1238 as Kincaith and in 1250 as Kincathe. The former spelling suggests derivation from Gaelic ceann ‘head’, ‘top’ + càithe ‘pass’, whereas the latter would point to cadha ‘quagmire’ as the second element.