In design of all kinds of power transmission gearing, also applicable to design of chain or toothed belt drives.

A "hunting tooth" is used to avoid gear ratios where the tooth count of one gear is an exact multiple of a gear it mates to (e.g. ratios 1:1, 2:1, 3:1 ...). The reason for avoiding integer gear ratios is that in such a design each tooth of the smaller gear always contacts exactly the same tooth or teeth in the gear it mates to. This in turn will cause accelerated wear, usually into an oval shape.

Thus if designing an (approximately) 2:1 gear ratio, the designer uses gears with 49 and 24 teeth respectively, then every tooth on each gear comes in contact with on it's mating gear. This in turn causes minor variations in wear to be propagated across all teeth.

In sprocket design, it is desirable to design for the chain or belt having a number of links which should not be evenly divisible by the number of teeth in any sprocket,