The invention concerns a bristle for a brush, in particular a cleaning brush, a toothbrush or an application brush, wherein the bristle has a lower root region with which it can be mounted in or to a bristle support or which forms part of the bristle support, and a free length disposed outside of the bristle support above the root region which is composed of a shaft region bordering the root region and a flexing region disposed thereabove, wherein the shaft region is composed of a lower shaft base section bordering the root region and a shaft section disposed thereabove, and wherein the flexing region is composed of a lower active and flexing section bordering the shaft region and a tip section which is disposed thereabove and forms the free end of the bristle, wherein the bristle has a continuous depression-free jacket in the shaft base section and, at least in sections of the jacket in the flexing region, a profiling which is formed by elevations and/or depressions and which lies in an outer surface of the bristle.