1. A short weapon used for stabbing. This is the general term: cf. Poniard, Stiletto, Bowie knife, Dirk, Misericorde, Anlace.
2. A mark of reference in the form of a dagger ‘ It is the second in order when more than one reference occurs on a page; called also obelisk.
(Science: zoology) dagger moth, any moth of the genus Apatalea. The larvae are often destructive to the foliage of fruit trees, etc. Dagger of lath, the wooden weapon given to the vice in the old Moralities. Double dagger, a mark of reference
Origin: cf. Oe. Daggen to pierce, f. Daguer. See dag a dagger.