keynote

nouns

the principal theme in a speech or literary work
is a part of
a speech setting forth the keynote
is a type of (narrower)
the subject matter of a conversation or discussion
"he didn't want to discuss that subject"; "it was a very sensitive topic"; "his letters were always on the theme of love"
a fundamental or central idea
is a type of (narrower)
the content of cognition; the main thing you are thinking about
"it was not a good idea"; "the thought never entered my mind"
(music) the first note of a diatonic scale

verbs

set the keynote of
"Comfort keynotes this designer's Fall collection"
is a type of (narrower)
put into a certain state; cause to be in a certain state
"set the house afire"
give the keynote address to (an audience)
is a type of (narrower)
give a speech to
"The chairman addressed the board of trustees"