Pear

n.
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.
Pear family (Bot.),
a suborder of rosaceous plants (Pomeæ), 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 (Zoöl.),
any marine gastropod shell of the genus Pyrula, native of tropical seas; -- so called from the shape.
Pear slug (Zoöl.),
the larva of a sawfly which is very injurious to the foliage of the pear tree.