patchboard vs plugboard

patchboard and plugboard both are nouns.

Word	Noun	Adjective	Verb	Adverb
patchboard	Yes	No	No	No
plugboard	Yes	No	No	No

As nouns, patchboard and plugboard are synonyms defined as:

patchboard and plugboard: telephone central where circuits are completed with patchcords

Other synonyms of patchboard include switchboard.

patchboard (noun)	plugboard (noun)
telephone central where circuits are completed with patchcords	telephone central where circuits are completed with patchcords