 U  |
| Under Bare Poles |
|
Having no sails up. In heavy weather the windage of the mast and other spars can still be enough to move the boat.
|
|
| Under the Lee |
|
On the lee side of an object, protected from the wind.
|
|
|
|
| Undertow |
|
Strong offshore current extending to the shore.
|
|
| Unfurl |
|
To unfold or unroll a sail. The opposite of furl.
|
|
| Upwind |
|
To windward, in the direction of the eye of the wind.
|
|
| Uscg |
|
United States Coast Guard.
|
|
