When a sailing vessel needs to travel in the direction the wind is blowing from, it cannot sail straight into the breeze. Instead, the crew must ply the vessel, sailing a zigzag course across the wind. This involves repeatedly changing direction so the wind strikes alternating sides of the bow, slowly gaining ground upwind.
Heard on the job
We had to ply up the narrow channel against a stiff northerly breeze all afternoon.
Also heard as
- beat
- tack