\Pear\ (p[^a]r), n. [OE. pere, AS. peru, L. pirum: cf. F.
poire. Cf. {Perry}.] (Bot.)
The fleshy pome, or fruit, of a rosaceous tree ({Pyrus
communis}), cultivated in many varieties in temperate
climates; also, the tree which bears this fruit. See {Pear
family}, below.
{Pear blight}.
(a) (Bot.) A name of two distinct diseases of pear trees,
    both causing a destruction of the branches, viz., that
    caused by a minute insect ({Xyleborus pyri}), and that
    caused by the freezing of the sap in winter. --A. J.
    Downing.
(b) (Zo["o]l.) A very small beetle ({Xyleborus pyri}) whose
    larv[ae] bore in the twigs of pear trees and cause them
    to wither.
{Pear family} (Bot.), a suborder of rosaceous plants
   ({Pome[ae]}), characterized by the calyx tube becoming
   fleshy in fruit, and, combined with the ovaries, forming a
   pome. It includes the apple, pear, quince, service berry,
   and hawthorn.
{Pear gauge} (Physics), a kind of gauge for measuring the
   exhaustion of an air-pump receiver; -- so called because
   consisting in part of a pear-shaped glass vessel.
{Pear shell} (Zo["o]l.), any marine gastropod shell of the
   genus {Pyrula}, native of tropical seas; -- so called from
   the shape.
{Pear slug} (Zo["o]l.), the larva of a sawfly which is very
   injurious to the foliage of the pear tree.