n.[C]

1. 钥匙
2. 图例；题解
3. （解决问题的）线索；秘诀；答案
   The detective believes the missing gun is the key to the mystery.

   那侦探认为那把丢失的枪是侦破这宗疑案的线索。

4. （钢琴，打字机等的）键
5. 【音】调
   The song is written in the key of D.

   这首歌是用D调谱写的。

6. 关键，要害；关键人物
   The quarterback was the key of their team.

   那四分后卫是他们队的灵魂人物。

   This is the key to world peace.

   这是世界和平的关键。

vt.

1. 锁上；插上
2. 【音】为……调音
   The musicians keyed their instruments just before the concert began.

   乐师们在音乐会快开始前为乐器调了音。

3. 用键盘输入（信息等）[（+in/into）]

a.

1. 重要的，基本的，关键的[B]
   Self-confidence is the key factor in any successful career.

   自信是任何成功之道的关键因素。

n.

1. a small piece of shaped metal with incisions cut to fit the wards of a particular lock, which is inserted into the lock and rotated to open or close it or to operate a switch.
   ▸an instrument for grasping and turning a screw, peg, or nut.
   ▸a pin, bolt, or wedge inserted into a hole or between parts so as to lock the parts together.
2. a lever depressed by the finger in playing an instrument such as the organ, piano, flute, or concertina.
3. each of several buttons on a panel for operating a typewriter, word processor, or computer terminal.
4. a lever operating a mechanical device for making or breaking an electric circuit.
5. a thing that provides access to or understanding of something:
   a key to success.
   ▸an explanatory list of symbols used in a map or table.
   ▸a set of answers to exercises or problems.
   ▸a word or system for solving a cipher or code.
   ▸the first move in the solution of a chess problem.
6. Music  a group of notes based on a particular note and comprising a scale, regarded as forming the tonal basis of a passage of music.
   ▸the tone or pitch of someone's voice.
7. the dry winged fruit of an ash, maple, or sycamore; a samara.
8. roughness on a surface, provided to assist adhesion of plaster or other material.
9. Basketball  the keyhole-shaped area marked on the court near each basket.

adj.

v.

1. enter or operate on (data) by means of a computer keyboard.
2. fasten into position with a pin, wedge, or bolt.
3. (key to) chiefly N. Amer. link with.
   ▸ (key into/in with) be connected or in harmony with.
4. (be keyed up) be nervous, tense, or excited.
5. roughen (a surface) to assist adhesion of plaster or other material.

n.