1. Pleasurable anal sex.

2.a. To have your sexual partner on all fours, in a doggy style position, and spin or grind their back door or ass around or into your penis.

2.b. To do the same with a sex toy or accessory.

3. To have your sexual partner on top while you lay flat and have them spin around on your penis.
"Tell me that you like it when you spin the back door" - Olivia, featuring Tony Yayo - You Already Know (Urban Music Track)
by yoshibai January 8, 2006
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