tack 1 
(tăk)
(tăk)n.
1. A short, light nail with a sharp point and a flat head.
2. Nautical
a. A rope for holding down the weather clew of a course.
b. A rope for hauling the outer lower corner of a studdingsail to the boom.
c. The part of a sail, such as the weather clew of a course, to which this rope is fastened.
d. The lower forward corner of a fore-and-aft sail.
3. Nautical
a. The position of a vessel relative to the trim of its sails.
b. The act of changing from one position or direction to another.
c. The distance or leg sailed between changes of position or direction.
4. An approach to accomplishing a goal or a method of dealing with a problem.
5. A large, loose stitch made as a temporary binding or as a marker.
6. Stickiness, as that of a newly painted surface.
v. tacked, tack·ing, tacks
v.tr.
1. To fasten or attach with a tack or tacks: tacked the carpet down.
2. To fasten or mark (cloth or a seam, for example) with a loose basting stitch.
3. To put together loosely and arbitrarily: tacked some stories together in an attempt to write a novel.
4. To add as an extra item; append: tacked two dollars onto the bill.
5. Nautical To bring (a vessel) into the wind in order to change course or direction.
v.intr.
1. Nautical
a. To change the direction of a sailing vessel, especially by turning the bow into and past the direction of the wind: Stand by to tack.
b. To sail a zigzag course upwind by repeatedly executing such a maneuver.
c. To change tack: The ship tacked to starboard.
2. To change one's course of action.
[Middle English tak, fastener, from Old North French taque, probably of Germanic origin.]
tacker n.
tackless adj.