Meaning: Very drunk, highly intoxicated.
Example: The groom made it to the alter, but he was three sheets to the wind.
Origin: The phrase comes from 18th-19th century English Naval terminology. The original phrase was " three Sheets in the wind" and referred to the erratic behavior of a ship that has lost control of all of its sails.
In nautical terminology sheets are the ropes that adjust the position of the sails relative to the wind.
The speed and direction of a sailing ship is controlled by the number of sails raised on each mast, the angle of the sails to the wind (trim of the sails), and the position of the rudder. If the sheets used to control the sails are to break or are have been released, the sheet is said to be "in the wind".
One can imagine a sail thrashing wildly in a strong wind with its sheet (the control ropes) blowing about. It would be very difficult to regain control of such a sail.
Prior to the 1810's it was common for ships to have three masts, (fore, main, and mizzen). If the sheets on all three masts are "in the wind", the ship loses all steering control.
The ship's lack of control is likened to that of a stumbling drunk.