Noun. A shortened form of the term mini-Balrog. From Lord of the Rings online fandom. Can also refer to "mini-Balrogs" in non-LOTR fandom, in which case it is a short form of, for example, a mini-Jem'Hadar (Star Trek), a mini-Aragog (Harry Potter), etc.
"Oh, look! Someone just made a mini of Aragorn--'Arasgorn'. Oh, cute little Arasgorn!"
1. A persons younger sibling; used most often when that younger sibling looks significantly like the older one.
Hinting they are a "mini" version of the older child.
-Can also be used when one person looks like another person.
2. Any child (much) younger than you.
Plural:
While I was passing the local elementry school, all I saw was a bunch of mini's running around the playground.