Webster's Revised Unabridged Dictionary · 1913

Crenelle

Crenelle (kr?-n?l") , noun

[Old French crenel, French cr{not transcribed}neau, Late Latin crenellus, kernellus, dim. (prob.) from Latin crena notch. See Crenny.]

1.
An embrasure or indentation in a battlement; a loophole in a fortress; an indentation; a notch. See Merlon, and Illust. of Battlement.
2.
(Botany) Same as Crenature.

Also: Crenel