Question

harry had not expected hermiones anger to abate overnight, and was therefore unsurprised that she communicated mainly by dirty looks and pointed silences the next morning.
source: harry potter and the deathly hallows
in the sentence above, abate has the same or almost the same meaning as:
debate
recede
heighten
solidify

Explanation:

"Abate" means to become less intense or to subside. "Recede" also implies a lessening or a withdrawing. "Debate" is about arguing, "heighten" is about increasing, and "solidify" is about making solid. So "recede" is the closest in meaning.

Answer:

recede