"Selection Sunday” is commonly known as the day college basketball teams are selected to participate in the NCAA Men’s Division I Basketball Championship Tournament, but the term also applies to women’s basketball and other sports as well. “Selection Sunday” has been cited in print since at least March 1985.
The name “Selection Sunday” has not been trademarked.
Wikipedia: NCAA basketball tournament selection process
Selection Sunday is the day when the NCAA College basketball tournament participants are placed, seeded accordingly, and announced. Both CBS and ESPN cover the selections for the men’s tournament live; ESPN also covers selections for the women’s tournament live on Selection Monday. The NCAA committee gathers to select and place 68 men’s teams and 64 women’s teams that secured or are deemed worthy of an invitation to the NCAA Men’s Division I Basketball Championship and the NCAA Women’s Division I Basketball Championship basketball tournaments that take place in March and April.
9 March 1985, Lexington (KY) Herald Leader, “Louisville falls 81-74 to Memphis,” pg. C1:
As for Louisville, however, last night probably cut Selection Sunday right out of the picture.
10 March 1985, The Oregonian (Portland, OR), “Sports on Radio,” TV Click, pg. 38, col. 1:
3 p.m. Selection Sunday: NCAA call-in program, KLIQ.
11 March 1985, Lexington (KY) Herald Leader, “Big Ten, Big East each get 6 bids,” pg. B1:
This wouldn’t be an NCAA Tournament, of course, without Selection Sunday producing at least a few puzzlements.
Google News Archive
1 March 1990, Milwaukee (WI) Journal, “Big 7 could find home in NCAA tournament” by John Schumacher, pg. 3C. col. 4:
It has become the biggest day in college basketball, a make-or-break time for seasons, dreams and careers.
In 10 days, coaches, players and fans will turn on televisions across America to see who goes where on the road to the Final Four.
New York (NY) Times—The Quad
March 17, 2013, 3:08 pm
Highlights and Analysis: Selection Sunday
By MIKE HUGUENIN
Empty brackets become a thing of the past today as the field of 68 is chosen for the 2013 men’s N.C.A.A. basketball tournament. Mike Huguenin is providing live updates and analysis.