keynote

 

English Wikipedia has an article on:

keynote

Wikipedia

From key +‎ note.

• (US) IPA^(key): /ˈkiːˌnoʊt/

• Audio (Southern England):

  (file)

keynote (plural keynotes)

1. A speech that sets the main theme of a conference or other gathering; a keynote speech or keynote address.
2. The main theme of a speech, a written work, or a conference.
3. (music) The note on which a musical key is based; the tonic.

• keynoter
• keynote speech

keynote (third-person singular simple present keynotes, present participle keynoting, simple past and past participle keynoted)

1. (transitive) To deliver a speech that sets the main theme of a conference or other gathering.

•   keynote on Wikipedia.Wikipedia