Pear \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.

Source: Webster's Revised Unabridged Dictionary (1913)