English

grism

Blend of grating + prism.

Proto-Indo-European *per-

Ancient Greek πρῐ́ω

Ancient Greek πρίσμᾰ ‘anything sawn’

Late Latin prisma ‘(geometry) prism’

English prism

Today it means

noun A combination of diffraction grating and prism used to obtain spectra from selected parts of an image.

Language periods are conventional ranges, not dates for this word.