twi-night

[twahy-nahyt]
adjective Baseball.
  1. pertaining to or noting a doubleheader in which the first game begins late in the afternoon and the second in the evening under lights.

Origin of twi-night

First recorded in 1945–50; twi(light) + night
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018