From Gaelic claidheamh beag "small sword". Attested 1825 (as Clay-beg).
claybeg (plural claybegs)
- the Scottish broadsword used during the Early Modern period
- 1835 "When Sir Walter Scott speaks, prior to 1715, of the inferiority of the claymore to the rapier, he refers not to the claybeg or Andrew Ferrara, now worn by the officers and sergeants of the Highland corps, and which has usurped the venerable name of the ancient Scottish weapon." (The United service magazine, letter to the editor, p. 109)
Usage notes 
Used as a term for the Scottish basket-hilted broadsword usually known as claymore by those who take the view that this is a misnomer, and that "claymore" is properly applied to the medieval two-handed sword only.
- Thomas Dudley Fosbroke, Encyclopædia of Antiquities: And Elements of Archaeology, Classical and Mediæval, Volume 2, 1825, p. 777.