also: combo · double team · deuce · duece
Two linemen on one defender. In a double team both of them stay; in a combo one of them leaves for a linebacker. Coaches use the words interchangeably and the difference is an entire assignment.
2 meanings, all below. Jump to the one you heard.
Two adjacent linemen block one defender and both finish on him. Nobody climbs. It is the most force football can apply to one man and it is what short yardage and goal line are built out of, where moving one defender two yards backward is the entire objective and there is no second-level defender worth releasing for.
deucecombo blockTwo linemen start on the same down defender, get him moving, and then one of them comes off to block a linebacker at the second level. The two-on-one is temporary and it is a means rather than an end.
The hard part is not the double team, it is the departure. Leave too early and the down lineman is suddenly one-on-one against a man who is already moving. Leave too late and the linebacker has run past the block and into the hole. Getting that timing right is most of what an offensive line spends its Tuesdays on, and a combo block that never climbs is the most common way a well-designed run play produces four yards instead of fifteen.
combination block, deuce/trey (as named by some staffs)double team, scoop blockMost coaches say double team when they mean combo. In practice the instruction that matters is whether anybody is climbing and when, so the useful question to a staff is not which word they use but who comes off and on what key.
At youth level the pure double team is often the better call even where a combo is drawn, because the climb is a timing skill that takes longer to teach than the season allows and a failed climb is worse than never leaving.