school day

nouns

any day on which school is in session
"go to bed early because tomorrow is a school day"
school day
is a type of (narrower)
a day assigned to a particular purpose or observance
"Mother's Day"
day
the period of instruction in a school; the time period when school is in session
"stay after school"; "he didn't miss a single day of school"; "when the school day was done we would walk home together"
school, school day, schooltime