What does “XWB” stand for in Airbus A350 XWB?

In Airbus A350 XWB, “XWB” stands for “Extra Wide Body.”

Airbus used the name to emphasize that the A350’s cabin was designed to be wider than the cabins of earlier Airbus wide-body aircraft such as the A330 and A340. The wider fuselage supports seating layouts intended to improve passenger comfort while retaining efficient long-range performance.

The A350 program originally evolved from an A330-based proposal, but Airbus later redesigned it substantially after airline customers requested a more capable and modern aircraft. The final A350 incorporated a new fuselage, new wings, composite structures and Rolls-Royce Trent XWB engines.

“XWB” is part of the aircraft’s historical marketing name, although Airbus commonly refers to the family simply as the A350 today. It does not mean an experimental version or a reference to Boeing; it describes the aircraft’s extra-wide-body cabin concept.