solar year vs astronomical year

solar year and astronomical year both are nouns.

Word	Noun	Adjective	Verb	Adverb
solar year	Yes	No	No	No
astronomical year	Yes	No	No	No

As nouns, solar year and astronomical year are synonyms defined as:

solar year and astronomical year: the time for the earth to make one revolution around the sun, measured between two vernal equinoxes

Other synonyms of solar year include equinoctial year, tropical year.

solar year (noun)	astronomical year (noun)
the time for the earth to make one revolution around the sun, measured between two vernal equinoxes	the time for the earth to make one revolution around the sun, measured between two vernal equinoxes