1. n. a rotten thing or person. Don’t be such a skag. Who do you think you are?
2. n. a very ugly woman. (Collegiate.) What a skag! I wouldn’t be seen with her.
3. n. a tobacco cigarette; a tobacco cigarette butt. (Military.) Can I bum a scag off you?
4. in. to smoke (a tobacco cigarette). He stopped scagging for about a week.
5. n. heroin, especially poor-quality heroin; any powerful drug. (Drugs.) Scag has sent a lot of my friends to the bone orchard.
6. n. hard liquor. The two of them put away a quart of my finest skag.