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1.
a pair of womens undies that are just a string(not thong)in the back,the strings makes a "T"
man i can see that chicks T-Back
by russ1416807 May 12, 2006
 
2.
Better than a thong, less floss, more like a G string/Thong combo. starts wide on the top, goes to string as soon as it hits the top of the ass crack.
Check that bitch's T BACK! DAAYUM!!
by Big Fat White Guy November 12, 2003
 
3.
Another word for g-string, thong style underwear. Originating in Japan. Often confused with t-bag by foreigners not used to Japanese pro-nun-see-A-shun.
You should wear your t-backs or you'll show your panty lines
by Zemble October 17, 2003