Texas Tuxedo

A “Texas tuxedo” might be the top half tux and the bottom half jeans and cowboy boots.
 
 
http://www.urbandictionary.com/define.php?term=texas+tuxedo
texas tuxedo
Denim jacket, denim jeans, often accompanied by a bolo tie and denim shirt. May include cowboy boots and/or cowboy hat.
see also: canadian tuxedo
Slim is dressed up for his birthday. Check out his Texas Tuxedo.
by pommedeterre Grand Rapids, MI Nov 3, 2005
 
   
http://www.majordojo.com/archives/000652.php
Texas oil tycoons are often depicted as wearing the famous “Texas Tuxedo:” blue jeans, boots, white shirt, a large belt buckle, a blazer or other fine jacket, a bolo tie, and a ten gallon hat6This is the term I learned when I was growing up in Austin, Texas. The outfit does indeed exist and is often worn to any number of formal social events, and in my experience, very acceptable in lieu of a real tuxedo..
 
 
Google Groups: alt.politics.libertarian
From:  Jim Kennemur
Date:  Sun, Oct 6 1996 12:00 am
 
He lives in the country near the northeast Texas town of Rice and
travels around the state in a well-worn Mazda. He appears in his
“Texas tuxedo”—dark jacket, white shirt, tie, blue jeans and
cowboy boots—before groups of the faithful who are trying to
rebuild the Republic of Texas government.
   
   
14 January 1981, Frederick (MD) News, pg. F3:
“This is a very disciplined football team. Now, we’re not the kind of team that is going to get off the airplane as the best-dressed group. John Bunting (linebacker) is going to look terrible. Jerry Sizemore (offensive tackle) is going to be in a Texas tuxedo. Guys will be in dungarees and a T-shirt. We are not hung up on all those things.”
 
 
19 February 2001, New York Times, “Back Home In Crawford And Having A Texas Ball” by Frank Bruni, pg. A11:
Many of them men were dressed in “Texas tuxedo”—formal jackets, shirts and bow ties with blue jeans and boots.