“Incongruous” sounds like “in Congress,” prompting the jocular definition:
 
“Incongruous: Where bills are passed.”
 
The language pun has been cited in print since at least 1995.
 
     
Google Groups dfw.singles
About last night. .
Randall Woodman
4/24/95
(...)
incongruous: Where bills are passed.
 
4 July 2003, Wisconsin State Journal (Madison, WI), “The Skinny,” pg. D1, col. 1:
Incongruous: Where bills are passed.
 
Google Books
Get Thee to a Punnery:
An Anthology of Intentional Assaults Upon the English Language
By Richard Lederer
Layton, UT: Wyrick & Company
2006
Pg. 119:
incongruous. Where bills are passed.
 
Google Books
Groan And Bear It
By Gary Younglove
Fair Oaks Ranch, TX: Piper Plus Publications
2010
Pg. 345:
Incongruous: Where bills are passed.
 
Facebook
Sheryl Underwood
December 28, 2012 ·
Pun time: Incongruous: Where bills are passed.
 
Google Books
Once Apun A Time:
A Rich, Historical and Sometimes Earthy Collection of Puns
By Robin Leech
Victoria, BC: FriesenPress
2015
Pg. 23:
Incongruous: Where bills are passed.
 
Twitter
Bill Helton
‏@7colonel7
Corny joke…What is Incongruous?  Where Bills are Passed!
11:58 PM - 15 Oct 2015
Alabama, USA