Scottish National Dictionary (1700–)
Hide Quotations Hide Etymology
About this entry:
First published 1968 (SND Vol. VII).
This entry has not been updated since then but may contain minor corrections and revisions.
†QUACK, n. Also kwack. A brief moment, a trice, in phr. in a quack, quick(ly) (Ork. 1882 Jam., Ork. 1967).
[Imit. of a short, sharp sound. Cf. Crack, n.1]