plate armor vs chamfron

plate armor and chamfron both are nouns.

Word	Noun	Adjective	Verb	Adverb
plate armor	Yes	No	No	No
chamfron	Yes	No	No	No

As nouns, chamfron is a hyponym of plate armor; that is, chamfron is a word with a more specific, narrower meaning than plate armor:

plate armor: specially hardened steel plate used to protect fortifications or vehicles from enemy fire
chamfron: medieval plate armor to protect a horse's head

plate armor (noun)	chamfron (noun)
specially hardened steel plate used to protect fortifications or vehicles from enemy fire	medieval plate armor to protect a horse's head
a historical type of personal armor made from iron or steel plates, which superseded mail during the 14th century.