tense vs nail-biting

tense is a noun but nail-biting is not a noun.

Word	Noun	Adjective	Verb	Adverb
tense	Yes	Yes	Yes	No
nail-biting	No	Yes	No	No

tense (noun)	nail-biting (noun)
a grammatical category of verbs used to express distinctions of time

tense (adjective)	nail-biting (adjective)
taut or rigid; stretched tight	(of a situation) characterized by or causing suspense
pronounced with relatively tense tongue muscles (e.g., the vowel sound in `beat')
in or of a state of physical or nervous tension

tense (verb)	nail-biting (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