mean solar day vs date

mean solar day and date both are nouns.

Word	Noun	Adjective	Verb	Adverb
mean solar day	Yes	No	No	No
date	Yes	No	Yes	No

As nouns, date is a hyponym of mean solar day; that is, date is a word with a more specific, narrower meaning than mean solar day:

Other hyponyms of mean solar day include tomorrow, today, yesterday, morrow, eve, day of the month, snow day.

mean solar day (noun)	date (noun)
time for Earth to make a complete rotation on its axis	sweet edible fruit of the date palm with a single long woody seed
	a meeting arranged in advance
	a participant in a date
	the specified day of the month
	the present
	the particular day, month, or year (usually according to the Gregorian calendar) that an event occurred
	a particular day specified as the time something happens

mean solar day (verb)	date (verb)
	assign a date to; determine the (probable) date of
	provide with a dateline; mark with a date
	stamp with a date
	go on a date with
	date regularly; have a steady relationship with