backing

n.倒退，支持物

back-pedal, back-up, back-yard, backache, backbite, backbiter, backbiting, backbone, backchat, backcloth, backcomb (also tease), backdate, backdrop, backer, backfire, backgammon, background, backhand, backhanded, backhander, backlash, backless, backlist, backlog, backpack, backpacker, backpacking, backrest, backscratcher, backset, backside, backslide, backsliding, backspace, backstage, backstroke, backtrack, backup, backward, backward(s),