Rar has 3 different meanings across 1 category:
Proper Noun
Noun
1
Alternative letter-case form of RAR
"I can't open that document because it's stuck in a corrupted .rar format."
Proper Noun
1
Acronym of Roshal Archive, a proprietary data compression format.
"The IT team spent hours trying to repair the corrupted .RAR file that contained all the project backups."