one who, or that which, primes-an instrument or device for priming; esp., a cap, tube, or water containing percussion powder or other compound for igniting a charge of gunpowder.-first; original; primary.-originally, a small prayer book for church service, containing the little office of the virgin mary; also, a work of elementary religious instruction.-a small elementary book for teaching children to read; a reading or spelling book for a beginner.-a kind of type, of which there are two species; one, called long primer, intermediate in size between bourgeois and small pica [see long primer]; the other, called great primer, larger than pica.