Thuggee (UK: , US: ) are actions and crimes carried out by Thugs, historically, organised gangs of professional robbers and murderers in India. The English word thug traces its roots to the Hindi ठग (ṭhag), which means 'swindler' or 'deceiver'. Related words are the verb thugna ('to deceive'), from the Sanskrit स्थग (sthaga 'cunning, sly, fraudulent') and स्थगति (sthagati, 'he conceals'). This term, describing the murder and robbery of travellers, was popular in the northern parts of the Indian subcontinent, especially northern and eastern regions of historical India (present-day northern/eastern India and Bangladesh). Contemporary scholarship is increasingly skeptical of the thuggee concept, and has questioned the existence of such a phenomenon, which has led many historians to describe thuggee as the invention of the British colonial regime.

Thugs were said to have travelled in groups across the Indian subcontinent. Thugs are said to have operated as gangs of highway robbers, tricking and later strangling their victims. To take advantage of their victims, the thugs would join travellers and gain their confidence, which would allow them to surprise and strangle the travellers with a handkerchief or noose. They would then rob and bury their victims. This led to the thugs being called Phansigar ("using a noose"), a term more commonly used in southern India. During the 1830s, the thugs were targeted for eradication by the Governor-General of India, Lord William Bentinck, and his chief captain, William Henry Sleeman.