Etymology Dictionary

KILT,  a very short petticoat worn by the Highlanders of Scotland.  (Scand.)   The sb. is merely derived from the verb kilt, to tuck up, added by Todd to Johnson's Dict.; he makes not mention of the sb.   'Her tartan petticoat she'll kilt,' i.e. tuck up; Burns, Author's Earnest Cry, st. 17.   'Kilt, to tuck up the clothes;' Brockett's North-Country Words.—Dan. kilte, to truss, tuck up. + Swed. dial. kilta, to swathe or swaddle a child (Rietz).   Cf. Icel. kilting, a skirt.   β. The verb is derived from a sb., signifying 'lap;' occurring in Swed. dial. kilta, the lap; cf. Icel. kjalta, the lap, kjöltu-barn a baby in the lap, kjöltu-rakki, a lap-dog.   The oldest form of the sb. occurs in Mœso-Goth. kilthei, the womb.   From the same root as E. Child, q.v.   ¶ Thus the orig. sense of kilt as a sb. is 'a lap,' hence 'tucked up clothes.' [†]

ADDENDA

Otherwise, it may be Celtic; see Cormac, Gloss. 47, s.v. celt.   Celt, vestis, raiment.   Cf. Irish cealt, clothes.   (A. L. Mayhew.)   I confess I doubt this; the explanation I have already given is more likely, as explaining both the Scottish kilt, to tuck up, and the Dan. kilte.   The kilt is not exactly 'clothes,' but only a particular part of the dress.  Rietz identifies the Swed. dialect kilträ sig, to tuck up one's clothes, with the Sc. to kilt up.