key; lock; key (to a problem, success, etc.); clue

Meaning

  1. n
    key
  2. n
    lock
  3. n
    key (to a problem, success, etc.); clue
  4. n
    key (on a piano, organ, etc.)

Example sentences

  • The key question is not what can I gain but what do I have to lose.

  • For code-type locks that don't need a key, there are 'free dial' systems where you can set any number you like, and fixed types where the number is set in advance.

  • I remember locking the door.