welly

In British English, a "welly" is an informal word for a Wellington boot, a tall waterproof boot usually made of rubber or a similar material. It is the kind of boot people wear on rainy days, on farms, in gardens, or at muddy festivals when they want to keep their feet dry. You will often hear the plural form, "wellies," because people usually talk about the pair.

The term "welly" is a friendly, informal British word for a Wellington boot, a tall waterproof boot that people wear in wet or muddy places. The name goes back to Arthur Wellesley, the first Duke of Wellington, because an early style of leather boot linked with him became well known in the 19th century. Later, when rubber boots became common, the name stayed and came to mean the waterproof boots many people still wear today.

People wear wellies for practical reasons: walking through puddles, working in the garden, spending time on farms, going to outdoor festivals, or taking the dog out in heavy rain. The image is strongly British, but the boots are used in many countries. They are often plain green or black, but they also come in bright colors and playful patterns, so they can feel fun as well as useful.

There is also a figurative British expression, "give it some welly," which means to put more force, energy, or effort into something. That might be physical, like kicking a ball harder, or more general, like attacking a job with real energy. So the word can point either to the boot itself or, in an idiomatic way, to a strong push of effort.