Definition of opponent for English Language Learners. : 1  a person, team, group, etc., that is competing against another in a contest. : 2  a person, group, etc., that is against something (such as an action, law, or system) : someone or something that does not want something to exist, be done, etc.
On the Celtic calendar, the traditional first day of winter is 1 November (Samhain, the Celtic origin of Halloween); spring starts 1 February (Imbolc, the Celtic origin of Groundhog Day); summer begins 1 May (Beltane, the Celtic origin of May Day); the first day of autumn is 1 August (Celtic Lughnasadh).
CLEVELAND, Ohio -- The first day of spring 2017 will be March 20, with winter officially ending at 6:28 a.m. that day. Summer 2017 will begin on June 21, fall on Sept. 22 and winter on Dec. 21. The first day of spring and fall each year marks the point when the length of days and nights are approximately equal everywhere on Earth. In Cleveland, day and night will each last very close to 12 hours a little ahead of the start of spring, on March 17, according to the U.S. Naval Observatory.