backbone

n.脊梁

back down/off, back number, back of, back out of, back road, back room, back seat, back talk, back up, back-bench, back-bencher, back-breaking, back-formation, back-pedal, back-up, back-yard, backache, backbite, backbiter, backbiting, backchat, backcloth, backcomb (also tease), backdate, backdrop, backer, backfire, backgammon, background, backhand, backhanded, backhander, backing, backlash, backless, backlist, backlog, backpack, backpacker, backpacking,