adj. having an edge or border indented with semicircles with points outwards. Usually the saltire and the dexter edge of the border of the shield both have cuts along their entire length the shape of crescent moons.
n. A European moth, Ectropis crepuscularia.
the GNU version of the Collaborative International Dictionary of English
adj. Indented with small concave curves, as the edge of a bordure, bend, or the like.
The Century Dictionary and Cyclopedia
In heraldry, cut into concave semicircular indents: said of a line and also of the bearing, such as a fesse, bordure, or the like, whose edge is broken in this way: as, a bordure engrailed. Also engreslé.
Word Usage
"The posterior half of the wing is the domain of expression of a molecule called engrailed, which is part of the machinery that makes the back half a back half."