fellatio vs sex

fellatio and sex both are nouns.

Word	Noun	Adjective	Verb	Adverb
fellatio	Yes	No	No	No
sex	Yes	No	Yes	No

fellatio (noun)	sex (noun)
oral stimulation of the penis	activities associated with sexual intercourse
	the properties that distinguish organisms on the basis of their reproductive roles
	all of the feelings resulting from the urge to gratify sexual impulses
	either of the two categories (male or female) into which most organisms are divided

fellatio (verb)	sex (verb)
	tell the sex (of young chickens)
	to evoke sexual feelings