On a mailing list I'm subscribed to, someone recently asked what the collective name was in English for the sharps and flats you find in the key signature. Apparently, the closest translation from several languages (German, Dutch, Russian) is "signs".
My first thought was "accidentals", but this doesn't match the more 'musical' definition of an accidental as a "note who's pitch has been altered from that given by the current key signature" (or something pretty close to that).
Any thoughts?