crown glass

noun

1. an optical glass of low dispersion and generally low index of refraction.

2. an old form of window glass formed by blowing a globe and whirling it into a disk.

crown glass

noun

1. another name for optical crown

2. an old form of window glass made by blowing a globe and spinning it until it formed a flat disc

Word History and Origins

Origin of crown glass¹

First recorded in 1700–10