A double-header originally referred to two consecutive baseball games played by the same two teams on the same day. Today, the term can apply to any two events or activities scheduled one after the other. Other synonyms for double-header include twin bill, twofer, back-to-back, and consecutive. These terms often connote a sense of efficiency or productivity, emphasizing the completion of two tasks in a short amount of time. In the entertainment industry, a double-header might refer to a concert or movie screening followed by a Q&A with the performers. In sports, it could describe a day with both a basketball and a hockey game in the same arena.