To fit (a lock) with a key.
To fit (pieces of a mechanical assembly) with a key to maintain the orientation between them.
To mark or indicate with a symbol indicating membership in a class.
(telegraphy and radio telegraphy) To depress (a telegraph key).
To operate (the transmitter switch of a two-way radio).
(more usually to key in) To enter (information) by typing on a keyboard or keypad.
Our instructor told us to key in our user IDs.
To vandalize (a car, etc.) by scratching with an implement such as a key.
He keyed the car that had taken his parking spot.
To link (as one might do with a key or legend).
To be identified as a certain taxon when using a key.
To modify (an advertisement) so as to target a particular group or demographic.
To attune to; to set at; to pitch.
To fasten or secure firmly; to fasten or tighten with keys or wedges.
In the sociology of Erving Goffman, an action or utterance that signals the meaning of interaction to participants.
The input of text or data by means of a keyboard.
A form of vandalism performed by scratching paint with a key