conception vs sex activity

conception and sex activity both are nouns.

Word	Noun	Adjective	Verb	Adverb
conception	Yes	No	No	No
sex activity	Yes	No	No	No

As nouns, sex activity is a hypernym of conception; that is, sex activity is a word with a broader meaning than conception:

conception: the act of becoming pregnant; fertilization of an ovum by a spermatozoon
sex activity: activities associated with sexual intercourse

Other hypernyms of conception include sex, sexual activity, sexual practice.

conception (noun)	sex activity (noun)
the act of becoming pregnant; fertilization of an ovum by a spermatozoon	activities associated with sexual intercourse
an abstract or general idea inferred or derived from specific instances
the creation of something in the mind
the event that occurred at the beginning of something