Semantic core
Also: keyword map
A structured list of search queries that the pages of your site are built to answer.
A semantic core is every query people might use to look for what you offer, gathered and sorted by meaning. In practice it is a list of customer questions your site prepares to answer.
Without a core, articles and pages are written blindly. With a core, each page answers a specific query that N people actually search for every month.
Full explainer
What a semantic core is →