tyre

1. The ring-shaped protective covering around a wheel which is usually made of rubber or plastic composite and is either pneumatic or solid. · pneumatic tyres· runflat tyres
2. The metal rim, or metal covering on a rim, of a (wooden or metal) wheel, usually of steel or formerly wrought iron, as found on (horse-drawn or railway) carriages and wagons and on locomotives. · iron tyres for the coach and iron shoes for the horse· tyres and rails of steel, and every axle with roller bearings

Plural tyres