\Mi"cro*pyle\, n. [Micro- + Gr. ? gate, orifice: cf.
F. micropyle.] (Biol.)
(a) An opening in the membranes surrounding the ovum, by
    which nutrition is assisted and the entrance of the
    spermatozoa permitted.
(b) An opening in the outer coat of a seed, through which the
    fecundating pollen enters the ovule. -- {Mi*crop"y*lar},
    a.