Grapefruit League (Grapefruit Circuit, Grapefruit Loop)

Baseball has spring training in Florida (among other places). The spring games have been termed the “grapefruit league” or “grapefruit circuit” or “grapefruit loop.”
 
   
The New Dickson Baseball Dictionary
by Paul Dickson
San Diego: Harcourt Brace & Company
1999
Pg.230:
grapefruit circuit Syn. of Grapefruit League.
Grapefruit League The name for the major-league teams that conduct spring training and play exhibition games against each other in Florida. Although the first team to make a southern spring training trip was the Chicago White Stockings who went to New Orleans in 1870, the first to train in Florida was the 1888 Washington Nationals, who went ot Jacksonville. Compare Cactus League. Syn. grapefruit circuit; grapefruit loop.
Etymology/1st Use. 1929.
grapefruit loop Syn. of Grapefruit League.
 
     
15 March 1923, Syracuse (NY) Herald, pg. 19:
It wasn’t a National League game such as Cincinnati will play after April 17, but it was a game in which Benton participated as a probably National League player and it created so much talk in the Red camp that a strong Eastern breeze sprung up to blow the news west to John A. Heydler, president of the National League, who is taking a vacation on the coast while Commissioner Landis is touring the Florida orange and grapefruit league.
 
 
26 March 1924, Washington Post, pg. S1:
PLANT CITY, Fla., March 25.—There is but little that baseball can give Donie Bush now. In addition to retaining the leadership the he enjoys at the head of the grapefruit league, the deposed boss of the Nationals gave his former underlings a tasty beating this afternoon.
   
 
27 April 1926, Clearfield (PA) Progress, pg. 5:
In the exhibition games the Boston Braves were the sensation of the Florida Grapefruit circuit while the Phillies had trouble winning a ball game from anybody.
 
 
21 March 1928, Los Angeles Times, pg. B4:
The spring training games don’t count in the pennant race, but it is worth noting, at least, that the St. Louis Cardinals, Browns, and Boston Braves have the best record in the grapefruit circuit so far while the world’s champion Yanks have the worst.
 
 
12 December 1930, Washington Post, pg. 16:
Big League Clubs Scramble Setup
Of “Grapefruit Loop” in Florida