keynote Meaning, Definition & Usage

  1. noun the principal theme in a speech or literary work
  2. noun a fundamental or central idea
  3. noun (music) the first note of a diatonic scale
    tonic.
  4. verb set the keynote of
    • Comfort keynotes this designer's Fall collection
  5. verb give the keynote address to (an audience)

WordNet

Key"note` noun
Definitions
  1. (Mus.) The tonic or first tone of the scale in which a piece or passage is written; the fundamental tone of the chord, to which all the modulations of the piece are referred; -- called also key tone.
  2. The fundamental fact or idea; that which gives the key; as, the keynote of a policy or a sermon.

Webster 1913