being of crucial importance; "a pivotal event"; "Its pivotal location has also exposed it to periodic invasions"- Henry Kissinger; "the polar events of this study"; "a polar principal"
the period of time that it takes for a planet (as, e.g., Earth or Mars) to make a complete revolution around the sun; "a Martian year takes 687 of our days"
a period of time containing 365 (or 366) days; "she is 4 years old"; "in the year 1920"
a period of time occupying a regular part of a calendar year that is used for some particular activity; "a school year"
the lagging of an effect behind its cause; especially the phenomenon in which the magnetic induction of a ferromagnetic material lags behind the changing magnetic field
presenting favorable circumstances; likely to result in or show signs or success; "propitious omens"; "propitious gales speeded us along"; "a propitious alignment of planets for space exploration"