鍵 - key

keyboard (of a piano, typewriter, etc.)

key

shared key

private account (on social media, esp. Twitter); account that can only be viewed by approved followers

symmetric key cryptography

key ring

cryptographic key; encryption key

key bed

black key (on a piano, organ, etc.)

key-shaped

private account (on social media, esp. Twitter); account that can only be viewed by approved followers

to lock (a door, etc.); to lock up