Seriously, what’s the significance of the word? There are many teens in my neighborhood, as well as me having a teenage sister, who laugh hysterically at the word.
Some people will respond with “Wanna know what else is massive?” Is this a sex joke or something?
[I live in the US now but grew up where many people did not speak English so I may not understand jokes that well even if my parents are English speakers.]
Edit: Looks like it’s from someone called Ninja. https://knowyourmeme.com/memes/ninjas-massive-you-know-what-else-is-massive
I can’t answer the question exactly just giving some thoughts.
Slang words these days are quick to rise and fall. Unless you’re in the in-group you’ll have a hard time figuring it out.
I’d recommend following this guy on any of the platforms, he tries to keep up with linguistic trends.