evening vs daytime

evening and daytime both are nouns.

Word	Noun	Adjective	Verb	Adverb
evening	Yes	No	No	No
daytime	Yes	No	No	No

As nouns, daytime is a hypernym of evening; that is, daytime is a word with a broader meaning than evening:

evening: the latter part of the day (the period of decreasing daylight from late afternoon until nightfall)
daytime: the time after sunrise and before sunset while it is light outside

Other hypernyms of evening include day, daylight.

evening (noun)	daytime (noun)
the latter part of the day (the period of decreasing daylight from late afternoon until nightfall)	the time after sunrise and before sunset while it is light outside
a later concluding time period
the early part of night (from dinner until bedtime) spent in a special way