\Sper`ma*to*zo"id\, n. [Spermatozo["o]n + Gr. ???
form.] (Biol.)
The male germ cell in animals and plants, the essential
element in fertilization; a microscopic animalcule-like
particle, usually provided with one or more cilia by which it
is capable of active motion. In animals, the familiar type is
that of a small, more or less ovoid head, with a delicate
threadlike cilium, or tail. Called also {spermatozo["o]n}. In
plants the more usual term is {antherozoid}.