The term 'Swazi' originates from the name of the 19th-century king, Mswati II, who was a paramount ruler and a key figure in the consolidation of the Swazi nation. The name 'Mswati' itself is derived from the SiSwati verb root '-swata', meaning "to be jealous" or "to guard jealously." Therefore, the ethnonym 'Swazi' literally translates to "the people of Mswati." As European colonial and linguistic contact increased, this indigenous name was adopted directly into English, first appearing in the mid-19th century to refer to the people, their kingdom (Swaziland, now Eswatini), and their language.

This is a proper noun adopted from the name of the people and their language. It is not productively formed from smaller, meaningful morphemes in English.