TACK

n. short pointed nail with a broad flat head; zigzag course of a ship sailing against the wind; sewing stitch used to temporarily fasten cloth together; riding gear (Equestrian); course of action

v. affix with a tack; append, add as an attachment; change course, alter one's direction (especially in a sailing vessel); sew together temporarily

Tack may refer to:Tack, a type of cut nail, used in upholstery, shoe making and saddle manufactureHorse tack, harness and equipment to allow horse-back ridingTack (sewing) (also baste or pin), quick, temporary stitching intended to be removedHardtack, a hard cracker or biscuit used for food on sea voyages and during the American Civil WarThumbtack or drawing pin, a short nail or pin easily placed and removed by handAugustus Vincent Tack (1870-1949), American painterIn sailing:Tacking, a maneuver by which a sailing boat turns its bow through the wind Tack (sailing), the lower corner of a sail's leading edge Tack (square sail), a type of rigging unique to square sails
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Noun
1. the heading or position of a vessel relative to the trim of its sails
(hypernym) bearing, heading, aim
(derivation) wear round
2. a short nail with a sharp point and a large head
(hypernym) nail
(hyponym) carpet tack
3. gear for a horse
(synonym) stable gear, saddlery
(hypernym) gear, paraphernalia, appurtenances
(hyponym) bit
4. (nautical) a line (rope or chain) that regulates the angle at which a sail is set in relation to the wind
(synonym) sheet, mainsheet, weather sheet, shroud
(hypernym) line
(hyponym) futtock shroud
(part-holonym) ship
(derivation) wear round
(classification) seafaring, navigation, sailing
5. (nautical) the act of changing tack
(synonym) tacking
(hypernym) change of course
(derivation) interchange, switch, alternate, flip, flip-flop
(classification) seafaring, navigation, sailing
6. sailing a zigzag course
(hypernym) sailing
Verb
1. fasten with tacks; "tack the notice on the board"
(hypernym) fasten, fix, secure
(hyponym) thumbtack
(see-also) append, tag on, tack on, hang on
2. turn into the wind; "The sailors decided to tack the boat"; "The boat tacked"
(synonym) wear round
(hypernym) sail
(derivation) sheet, mainsheet, weather sheet, shroud
(classification) boat
3. make by putting pieces together; "She pieced a quilt"; "He tacked together some verses"
(synonym) assemble, piece, put together, set up, tack together
(hypernym) join, bring together
(hyponym) confect, confection, comfit
4. sew together loosely, with large stitches; "baste a hem"
(synonym) baste
(hypernym) sew, run up, sew together, stitch
(derivation) baster, tacker
5. fix to; attach; "append a charm to the necklace"
(synonym) append, tag on, tack on, hang on
(hypernym) attach
(hyponym) subjoin
6. reverse (a direction, attitude, or course of action)
(synonym) interchange, switch, alternate, flip, flip-flop
(hypernym) change by reversal, turn, reverse
(derivation) tacking

(v. t.)
To fasten or attach.
  

(v. t.)
To change the direction of (a vessel) when sailing closehauled, by putting the helm alee and shifting the tacks and sails so that she will proceed to windward nearly at right angles to her former course.
  

(v. t.)
The part of a sail to which the tack is usually fastened; the foremost lower corner of fore-and-aft sails, as of schooners (see Illust. of Sail).
  

(v. t.)
The direction of a vessel in regard to the trim of her sails; as, the starboard tack, or port tack; -- the former when she is closehauled with the wind on her starboard side; hence, the run of a vessel on one tack; also, a change of direction.
  

(v. t.)
In parliamentary usage, to add (a supplement) to a bill; to append; -- often with on or to.
  

(v. t.)
Especially, to attach or secure in a slight or hasty manner, as by stitching or nailing; as, to tack together the sheets of a book; to tack one piece of cloth to another; to tack on a board or shingle; to tack one piece of metal to another by drops of solder.
  

(v. t.)
Confidence; reliance.
  

(v. t.)
A rope used to hold in place the foremost lower corners of the courses when the vessel is closehauled (see Illust. of Ship); also, a rope employed to pull the lower corner of a studding sail to the boom.
  

(v. t.)
A contract by which the use of a thing is set, or let, for hire; a lease.
  

(v. i.)
To change the direction of a vessel by shifting the position of the helm and sails; also (as said of a vessel), to have her direction changed through the shifting of the helm and sails. See Tack, v. t., 4.
  

(n.)
That which is attached; a supplement; an appendix. See Tack, v. t., 3.
  

(n.)
A stain; a tache.
  

(n.)
A small, short, sharp-pointed nail, usually having a broad, flat head.
  

(n.)
A peculiar flavor or taint; as, a musty tack.
  

Tack is a metaphor used sometimes on PMTH to replace Lyotard's concept of a "ruse" which is one of the ingredients of paralogy .  Tacking is the manouever that is performed when the boat changes from one tack to the other. This involves the boat turning through about 90-100°, with the wind passing around the bows (front) of the boat.  Normally this is done repeatedly, say once every 5 minutes in a dinghy race in order to progress to windward. For instance if one wishes to reach a bouy that is directly in the dircetion in which the wind is coming from, the boat is sailed close hauled on one tack, and then close hauled on the other tack.