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).
The winter solstice is the year's shortest day, but the start of winter also launches the sun's steady climb toward the long, warm days of summer. This year, the northern winter solstice occurs on Wednesday, December 21, at 5:44 a.m. ET (10:44 UTC). It happens at the same moment no matter where you live, but because we've divided Earth into 24 times zones, people around the world will observe it at 24 different times of day.