To botch something means to mess it up badly through carelessness or poor skill. When you botch a task, you don't just make a small mistake: you bungle it so thoroughly that the results are obviously wrong or unusable.

A student might botch an art project by using way too much glue, making the paper wrinkle and tear. A cook could botch a cake by misreading the recipe and adding salt instead of sugar. In each case, the person had a job to do but did it so poorly that they created a mess.

The word suggests more than simple failure. When you botch something, you usually had the chance to do it right but got careless, rushed through it, or didn't pay attention to important details. A botched repair job might make things worse than they were before. A botched attempt to fix a bicycle might leave it with loose bolts and a crooked wheel.

People sometimes say “don't botch it!” when warning someone to be careful with an important task. The word carries a sense of disappointment: the work could have been done well, but instead it turned into a disaster.