IPA: /ˈkjuːmjʊlətɪvli/
KK: /ˈkjuːmjʊlətɪvli/
In a way that adds up or increases over time, often referring to the total amount resulting from a series of additions.
The points from each game are added cumulatively to determine the overall winner.
Cumulatively → It is formed from "cumulus" (from Latin, meaning heap or pile) and the suffix "-ively" (meaning in a manner of). The word "cumulatively" refers to something that is done in a manner that accumulates or builds up over time.
Think of a 'heap' ('cumulus') that grows larger as things are added 'in a manner' ('-ively') — that's how cumulatively means building up over time.