visor vs armour plate

visor and armour plate both are nouns.

Word	Noun	Adjective	Verb	Adverb
visor	Yes	No	No	No
armour plate	Yes	No	No	No

As nouns, armour plate is a hypernym of visor; that is, armour plate is a word with a broader meaning than visor:

visor: a piece of armor plate (with eye slits) fixed or hinged to a medieval helmet to protect the face
armour plate: specially hardened steel plate used to protect fortifications or vehicles from enemy fire

Other hypernyms of visor include armor plate, armor plating, plate armor, plate armour.

visor (noun)	armour plate (noun)
a brim that projects to the front to shade the eyes	specially hardened steel plate used to protect fortifications or vehicles from enemy fire
a piece of armor plate (with eye slits) fixed or hinged to a medieval helmet to protect the face