tropical years

Noun

tropical year (plural tropical years)

1. The time that it takes for the Sun to return to the same position along the ecliptic, as viewed from the Earth, especially, completing a full cycle of seasons.
2. A vernal equinox year; the time between two successive vernal equinoxes.

   Synonyms:

   solar year, astronomical year, equinoctial year, Sothic year

3. (broadly) The time it takes for any astronomical object (such as a planet, dwarf planet, small Solar System body, or comet) in direct orbit around a star (such as the Sun) to make one revolution around the star, taking into account orbital precession.