alarm vs unalarming

alarm is a noun but unalarming is not a noun.

Word	Noun	Adjective	Verb	Adverb
alarm	Yes	No	Yes	No
unalarming	No	Yes	No	No

alarm (noun)	unalarming (noun)
a device that signals the occurrence of some undesirable event
a clock that wakes a sleeper at some preset time
an automatic signal (usually a sound) warning of danger
fear resulting from the awareness of danger

alarm (adjective)	unalarming (adjective)
	not alarming; assuaging alarm

alarm (verb)	unalarming (verb)
warn or arouse to a sense of danger or call to a state of preparedness
fill with apprehension or alarm; cause to be unpleasantly surprised