BACKLASH n.
The distance through which one part of connected machinery, as a wheel, piston, or screw, can be moved without moving the connected parts, resulting from looseness in fitting or from wear; also, the jarring or reflex motion caused in badly fitting machinery by irregularities in velocity or a reverse of motion.…
FLASHING n. 4 definitions
A mode of covering transparent white glass with a film of colored glass. Knight. Flashing point (Chem.), that degree of temperature at which a volatile oil gives off vapor in sufficient quantity to burn, or flash, on the approach of a flame, used as a test of the comparative safety of oils, esp. kerosene; a flashing po…