cover glass

a thin, round or square piece of glass used to cover an object mounted on a slide for microscopic observation.

Also called cover slip.

Origin of cover glass

First recorded in 1880–85

Touch the center of a cover-glass to the top of the drop and quickly place it, blood side down, upon a slide.

A Manual of Clinical Diagnosis |James Campbell Todd
Large drops are quite useless, for with them, the one cover-glass swims on the other, instead of adhering to it.

Histology of the Blood |Paul Ehrlich
Place a drop of water containing Paramœcia on a slide with cover-glass over it.

Elementary Zoology, Second Edition |Vernon L. Kellogg
Dip the cover-glass into a beaker containing hot water in order to remove some of the vaseline adhering to it.

The Elements of Bacteriological Technique |John William Henry Eyre

When considerable numbers are present, they can be detected and often identified in cover-glass smears.

A Manual of Clinical Diagnosis |James Campbell Todd

cover glass

a thin square of mounted glass used to protect a photographic slide