1. (nautical) at the ends of the transverse deck beams of a vessel; - Example: "on her beam-ends" means heeled over on the side so that the deck is almost vertical;
WordNet (r) 3.0 (2006):
beam-ends
n 1: (nautical) at the ends of the transverse deck beams of a
vessel; "on her beam-ends" means heeled over on the side so
that the deck is almost vertical