Emily Dickinson Lexicon

key (-s), n¹. [OE cæg.] (webplay: finger's, frame, lock, played, shutting).

1. Connection; emblem; symbol; sign; signal; thing that opens or closes the way to something.
2. [Fig.] power of custody; assess; control; admission by possession of the keys of any place; [lit.] mechanism or process for sealing a grave or casket.
3. [Fig.] fundamental note; basic tone to which a piece of music is accommodated.
4. [Fig.] levers in an organ, pianoforte, etc.; segments of an instrument which the fingers press down to produce musical notes.