n.

1. 平頭釘，大頭釘；圖釘[C]
   Joe hammered a tack into the wall to hang a picture.

   喬用錘子把一只大頭釘敲進牆中用來掛一幅畫。

2. 粗縫針腳；假縫[C]
3. 【船】（帆的）上下腳；上下角索[C]
4. 【海】（帆船的）航向[C]
5. 行動步驟，方針[U][C]
   If you can't persuade him, try a new tack.

   如果你不能勸服他，那就試試新的方法吧。

6. 黏性，黏著力[U]

vt.

1. 用平頭釘釘[（+down）]
   We tacked some posters on the wall.

   我們把一些海報釘在牆上。

2. 暫時用粗針腳縫
3. 附加，增補[（+to/on/onto）]
   They've tacked a couple of new clauses on to the end of the contract.

   他們在合同的末尾加了兩條新的條款。

4. 使（船）搶風轉變航向

vi.

1. 搶風轉變航向
   The sailing ship was tacking.

   帆船一路換搶航行。

2. 改弦易轍，改變方針

n.

1. a small, sharp broad-headed nail.
   ▸N. Amer. a drawing pin.
2. a long stitch used to fasten fabrics together temporarily, prior to permanent sewing.
3. a course of action:
   there is no reason for them to change tack now.
4. Sailing  an act of tacking.
   ▸a boat's course relative to the direction of the wind.
5. Sailing  a rope for securing the corner of certain sails.
   ▸the corner to which such a rope is fastened.
6. the quality of being sticky.

v.

1. fasten or fix with tacks or with temporary long stitches.
2. (tack something on) add something to something already existing.
3. Sailing  change course by turning a boat's head into and through the wind.
   ▸make a series of such changes of course.

n.

n.