duplex vs bidirectional

duplex is a noun but bidirectional is not a noun.

Word	Noun	Adjective	Verb	Adverb
duplex	Yes	Yes	Yes	No
bidirectional	No	Yes	No	No

duplex (noun)	bidirectional (noun)
an apartment having rooms on two floors that are connected by a staircase
a house with two units sharing a common wall

duplex (adjective)	bidirectional (adjective)
allowing communication in opposite directions simultaneously	reactive or functioning or allowing movement in two usually opposite directions
(used technically of a device or process) having two parts

duplex (verb)	bidirectional (verb)
change into a duplex