(databases) primary key

the ten keys of a keypad

(idiomatic) A piece of cake; an extremely simple thing, something trivial, a cinch, easy as pie.

朝飯前: A piece of cake; an extremely simple thing.

(telephony) a common Japanese telephone greeting: hello; used when answering the telephone / used to confirm that the person being addressed is listening, or to confirm if anyone is listening

put away

lose a person, suffer the death of another person

Key lime, Citrus × aurantiifolia

to lose (something) / to get rid of / to lose (someone) (wife, child, etc.)

key chain, keychain; key ring, keyring