A form of hand-to-hand combat weaponary, that fits around a persons fingers, to increase the amount of damage created with a punch. These are usually metal.
John: "How come your face is cut?"
Mark: "Adam hit me with knuckledusters on."
by IKane June 12, 2006
Someone who farts with a finger in their Ass. Knuckledusting isn't sexual in nature, it is much more closely related to fart sniffing or other Anal Olympic Events. There is a correlation between this activity and growing up in a trailer. This activity was almost certainly invented in the 70's when video games were all but non-existent and drugs were, well, the same as today
Anybob: Hey Bubba!
Bubba: Awwwe haw
Anybob: Putcho fanger in mah butt ho
Bubba: Awwwe haw
Anybob: BRRAAAAAAARRRKKKTTtttwwweeeeeeuuuuueeee!
Bubba: Awwwe mayn! Yuz a low down no good knuckleduster! Hurr hurr hurr!!!
by funk potato September 4, 2009
When someone accidentally brushes your genitals with their hand.
When Brian accidentally knuckledusted him, Ben didn't mind, as he was a homosexual.

"Dude, don't knuckledust me."
by missbehaved August 11, 2008
When a loved one or significant other won't help a bro out and he's forced to knuckle his own junk. Said bro shoots baby batter into his own hand and allows it to dry. The following morning punches the unwillingly participant from the night before creating an eruption of cum dust shooting from his knuckles.
Liz wouldn't go down on mike, so he gave her a full-on knuckledusting the next morning.
by Georgiamrlory July 20, 2010
When a man ejaculates onto his first before punching his partner in the face with the be-seamened hand!
The bitch was complaining about my rough treatment of her, so I gave her the ol' pearl knuckleduster!
by boofstien March 2, 2012
Jim said his dick was bruised, because he got a knuckleduster from a circus freak show.
by smingleton May 7, 2019