1. Not doing very much of anything.

2. Not doing what you are meant to be doing.
Stop slacking off Steve
by PowerGlide May 9, 2015
Slacking off at this time, when there's so much to do? (to slack off)
by anything more November 21, 2011
The act of one giving themselves an over-the-pants handie, whereas they are either unable or too lazy to pull their pants down and masturbate correctly.
"This morning at work John was totally caught slacking-off under his desk."

"I always slack-off at dinner on the first date."
by StonyBear November 10, 2011
To masturbate, jack off, stroke your penis, fap, beat your wiener, play with yourself,
My penis was a boner so I slacked off.
slack off.
by Minecraft1238 February 8, 2019
When you have a computer and unblocked games are working 😈 😈 😈 😈
Are you "slacking off school"?
by Cryptic hacker 😈 October 11, 2021