Device for igniting the powder in a firearm such as a musket. Developed 1515, the wheel lock struck a spark to ignite powder in the pan of a musket by means of a holder that pressed a shard of flint or a piece of iron pyrite against an iron wheel with a milled edge; the wheel rotated and sparks flew. The principle was used in the design of the flint-and-wheel cigarette lighter. See also flintlock