triple-header

[trip-uh l-hed-er]
noun Sports.
  1. a set of three games, as of basketball, each game being played in the same arena on the same day and often between different pairs of teams.

Origin of triple-header

First recorded in 1945–50
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018