E. Cobham Brewer 1810–1897. Dictionary of Phrase and Fable. 1898.
Grebenski Cossacks.
So called from the word greben (a comb). This title was conferred upon them by Czar Ivan I., because, in his campaign against the Tartars of the Caucasus, they scaled a mountain fortified with sharp spurs, sloping down from its summit, and projecting horizontally, like a comb. (Duncan: Russia.)
