Fulling or tucking or walking ("waulking" in Scotland) is a step in woolen clothmaking which involves the cleansing of cloth (particularly wool) to eliminate oils, dirt, and other impurities, and making it thicker. The worker who does the job is a fuller, tucker, or walker. The Welsh word for a fulling mill is pandy, which appears in many place-names.

Fulling involves two processes, scouring and milling (thickening). Originally, fulling was carried out by pounding the woolen cloth with the fuller's feet, or hands, or a club. In Scottish Gaelic tradition, this process was accompanied by waulking songs, which women sang to set the pace. From the medieval period, however, fulling often was carried out in a water mill.

These processes are followed by stretching the cloth on great frames known as tenters, where it is held onto those frames by tenterhooks. It is from this process that the phrase being on tenterhooks is derived, as meaning to be held in suspense. The area where the tenters were erected was known as a tenterground.