1) having guts or balls
2)the "behind the scenes" guy(s) of an outfit or group who do a signficant contribution to something but don't get as much recognition. Second only to the heart and soul.
1) You've got to grow a backbone if you don't want to become the one who gets trampled over in the end.
2) If she's the heart and soul of the group, then those two are the backbone of it.
you need to let me behind ya backbones
The sometimes pleasureful event in which a male becomes erect while spooning with a female.
Dude, last night I got a backbone while spooning with Charlotte! It was awkward at first, but then she started using her spine to rub my erect manhood!