prism vs optical device

prism and optical device both are nouns.

Word	Noun	Adjective	Verb	Adverb
prism	Yes	No	No	No
optical device	Yes	No	No	No

As nouns, optical device is a hypernym of prism; that is, optical device is a word with a broader meaning than prism:

prism: optical device having a triangular shape and made of glass or quartz; used to deviate a beam or invert an image
optical device: a device for producing or controlling light

prism (noun)	optical device (noun)
optical device having a triangular shape and made of glass or quartz; used to deviate a beam or invert an image	a device for producing or controlling light
a polyhedron with two congruent and parallel faces (the bases) and whose lateral faces are parallelograms