in series vs asynchronous

in series and asynchronous both are adjectives.

Word	Noun	Adjective	Verb	Adverb
in series	No	Yes	No	No
asynchronous	No	Yes	No	No

in series (adjective)	asynchronous (adjective)
of or relating to the sequential performance of multiple operations	not synchronous; not occurring or existing at the same time or having the same period or phase
	(digital communication) pertaining to a transmission technique that does not require a common clock between the communicating devices; timing signals are derived from special characters in the data stream itself