A mule is a specialized triangular sail flown high up between the main and mizzen masts on two-masted yachts like ketches and yawls. It acts effectively as a mizzen staysail to catch higher wind currents that the lower sails miss. Sailors deploy it to squeeze extra speed out of a reaching or running course in light to moderate winds.
Heard on the job
The wind is dropping, so let's hoist the mule and see if we can catch a bit more drive.
Also heard as
- mizzen staysail