tropical year

And now, by a variety of indications, it was manifest that the winter of the tropical year was at hand.

This would indeed be the case if the mean value of the civil year of the Julian calendar was exactly equal to the tropical year.

By taking this amount from the sidereal we obtain the tropical year, which has reference to the seasons and the calendar.

This is the tropical year or the time from one equinox to its return.

Have you ever quite realized what the tropical year is like?