Entomology definition of Vagina: the tubular structure formed by the union of
the oviducts in the female, opening externally to admit the
passage of the egg to the ovipositor: receives the penis of the
male in copulation and is sometimes called oviduct: “every part,
the office of which is to cover, protect or defend the tongue”:
“the bivalve coriaceous sheath or cover of the spicula”:
generally, a sheath.