highly strung vs tense

highly strung is not a noun while tense is a noun.

Word	Noun	Adjective	Verb	Adverb
highly strung	No	Yes	No	No
tense	Yes	Yes	Yes	No

highly strung (noun)	tense (noun)
	a grammatical category of verbs used to express distinctions of time

highly strung (adjective)	tense (adjective)
being in a tense state	taut or rigid; stretched tight
	pronounced with relatively tense tongue muscles (e.g., the vowel sound in `beat')
	in or of a state of physical or nervous tension

highly strung (verb)	tense (verb)
	cause to be tense and uneasy or nervous or anxious
	become tense, nervous, or uneasy
	increase the tension on
	become stretched or tense or taut