Sarah and I have been playing Mercs on RE5 for a while on her PS3 (given I don't actually own the game) playing as Wesker and Jill (not surprisingly, we get top marks most of the time :P) and we've come to give the enemies nicknames which gives us a laugh in between cursing at them when they abuse and try to hit us. :D
Blinky
Chuckles
Party Boy
Po-Po or Bad, bad Christian
Smiley
Slim
"What Yo Momma Say?" (because it sounds like they are saying that when they attack you :p)
We have other ones too that I couldn't find clear/good pictures of.
Female Town Majini (the ones with the Wicked Witch of the West laugh)-Vega Bitch because that's what she sounds like she's saying, "Vega, vega, vega!". :P
Clam/flower-headed Majini- Clambake
Wetlands Majini with firey arrows- Arsonist
Any other Wetlands Majini- T.R.S (Token Racial Stereotype)