summon vs summons

summon is not a noun while summons is a noun.

Word	Noun	Adjective	Verb	Adverb
summon	No	No	Yes	No
summons	Yes	No	Yes	No

As verbs, summon and summons are synonyms defined as:

Other synonyms of summon include cite.

summon (noun)	summons (noun)
	a writ issued by authority of law; usually compels the defendant's attendance in a civil suit; failure to appear results in a default judgment against the defendant
	a request to be present
	an order to appear in person at a given place and time

summon (verb)	summons (verb)
make ready for action or use	call in an official matter, such as to attend court
call in an official matter, such as to attend court
ask to come
gather or bring together
cause to become available for use, either literally or figuratively