noun

1. a flowing or flow
2. the rate of flow of water, as the tide or current, through a defined area
3. a continuous movement or continual change fashion is always in a state of flux
4. any excessive or unnatural discharge of fluid body matter, esp. from the bowels
5. 1. a substance, as borax or rosin, used to help metals fuse together by preventing oxidation, as in soldering
   2. in metallurgy, a substance added to metals while they are in a furnace, to remove impurities, promote fusing, etc., as a non-metallic material added to a furnace charge that has the ability to fuse with undesired matter and form a liquid slag that can run off more easily
6. Physics the rate of flow of energy, fluids, etc. across a surface

Etymology: ME < OFr < L fluxus, a flowing, flow < pp. of fluere, to flow: see fluctuate

transitive verb

1. to make (a solid) melt
2. to fuse (metals) by melting

intransitive verb