A girl that lacks morals. She has had many sexual encounters with the opposite sex and possibly has an STD. These girls tend to sleep with everyone with the exception of their boyfriend. These girls are also flirty, and they often treat guys in a greasy manner. The girls that do this often do it to boost their ego. Basically another word for the common slut.
Joe: I heard that girl has dick sucking marathons with her roommate.
Kieth: Yeah man. I wouldn't be surprised if she has something. Shes a slogg.
An fish usually larger than the blue whale, has a pickle shapped body and small legs or fins. With the great size of the Slogg many minerals collect on thier backs in great amounts, thus motivating people to setup UWSMMM's (under water skin mounted mineral mines) (the dangling leg type of Slogg can be found on Star Craft (Overlord), and the fin type can be found on a few Star Wars games in the underwater areas)
And behold, they did hunt the great King Slogg to setup a UWSMMM. Sloggs Ch2 Verse 45