Bible Dictionaries
Keynote

Webster's Dictionary

(1):

(n.) 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):

(n.) The fundamental fact or idea; that which gives the key; as, the keynote of a policy or a sermon.

Bibliography Information
Webster, Noah. Entry for 'Keynote'. Noah Webster's American Dictionary. https://www.studylight.org/​dictionaries/​eng/​web/​k/keynote.html. 1828.