contemporaneous vs synchronous

contemporaneous and synchronous both are adjectives.

Word	Noun	Adjective	Verb	Adverb
contemporaneous	No	Yes	No	No
synchronous	No	Yes	No	No

contemporaneous (adjective)	synchronous (adjective)
of the same period	occurring or existing at the same time or having the same period or phase
occurring in the same period of time	(digital communication) pertaining to a transmission technique that requires a common clock signal (a timing reference) between the communicating devices in order to coordinate their transmissions