The word "castors" is correct in written English.
It is used to refer to small wheels or rollers attached to the bottom of furniture or equipment to facilitate movement.
Example: "The office chair is equipped with castors for easy mobility."
Alternatives: "Wheels" or "Rollers".
For adults in 1960s Britain, they were Nazis on castors.
Tente specialises in castors for hospital beds.
Common varieties were circular or oval, hooped with brass bands, and provided with tapered, fluted legs with castors.
French explorers called it Île du Castor (for the castors [beavers] found there), and a French settlement (abandoned 1603) was one of the earliest in the area.
Certain alkalies and organic solvents, however, will attack linoleum if left in prolonged contact; staining and discoloration can arise from certain anti-oxidants in tires, rubber castors, or rubber heels.
Bloom £300 Johnlewis.com Solid birchwood; two mattress heights, can be folded and assembled quickly and has four lockable castors for easy manoeuverability.
In a wet year, peanuts give the best returns, but if the rains are poor, the more drought-tolerant castor is a better bet.
Now, 15 federal ministries are pondering every conceivable consequence of paving the road, from greater prostitution to opportunities for organic derivatives of castor oil.
Why this should be so is usually explained by two things: the gyroscopic precession caused by the spinning front wheel, and the castor effect resulting from the front wheel's contact point with the road trailing behind the steering axis of the front forks—in much the same way that the trailing wheels of a shopping trolley allow it to be steered easily.
To understand what is really needed to make a bicycle self-stablising, a team headed by Jodi Kooijman of Delft University of Technology in the Netherlands, several years ago took a simplified version of the Whipple model and set both the gyroscopic terms and the trail to zero, thereby eliminating both gyro and castor.
One firm, for example, has devised a way to make glue using oil from locally-grown castor beans instead of petroleum-based chemicals.
