Top definition
The act of attempting to slyly hide an acquired erection in a place of public persons.
"Although Bret tries to cover it up, we know he's got a Sly Hallacy."
by SlyDawg69 May 15, 2010
Mug icon

The Urban Dictionary Mug

One side has the word, one side has the definition. Microwave and dishwasher safe. Lotsa space for your liquids.

Buy the mug

Alphabetical list