What is the rubber, plastic or metal cap at the ground end of a walking stick called?

A ferrule is ring or cap which strengthens the end of a handle, stick, or tube and prevents it from splitting, fraying or wearing. The (mostly) rubber ferrule on the end of a walking stick or cane also reduces slippage in addition to prevention of ‘wear and tear’.

The term ‘ferrule’ applies to a wide range of devices and objects, generally used for fastening, joining, sealing or reinforcement applications. For example, in sports, golf clubs, fishing rods and cues make use of ferrules in their construction. In engineering, cable housings, connectors, electrical insulators and tool manufacture all utilise ferrules. In art and music respectively, ferrules are used in making brushes and violin bows. In medicine, hypodermic syringes employ specialist ferrules as does restorative dentistry.

The word ‘ferrule’ derives from ‘verrel’ or ‘verril’ in which form the word was used until the 18th century. This was derived in turn from the Old French ‘virelle’ which in turn derived from the Latin ‘viriola’ meaning small bracelet. The form of the word changed due to the influence of the Latin word ‘ferrum’, meaning iron, the medium in which verrels were most often cast.

The word ‘ferule’ is a term for an instrument formerly used to punish children in days long gone by. The use of the stalk of the ‘ferula’ (giant fennel plant) as a cane or rod for punishment, led sometimes to the ordinary cane wielded by many a past schoolmaster being referred to as the ‘ferule’.