IPA: /ˈmæsɪvli/
KK: /ˈmæsɪvli/
In a way that is very large or significant.
The project was massively successful, exceeding all expectations.
Massively → It is formed from "mass" (from Latin *massa*, meaning a lump or bulk) and the suffix "-ively" (meaning in a manner of). The word "massively" means in a manner that is large or substantial, often referring to size or extent.
Think of something that is a large 'lump' or 'bulk' ('mass') and how it is done 'in a manner' ('-ively'). This helps you remember that 'massively' describes something done in a large or substantial way.