'dreadlock' originates from English, a compound of 'dread' and 'lock', where 'dread' comes from Old English (meaning 'fear') and 'lock' comes from Old English 'locc' (meaning 'a curl or tress of hair').

'dreadlock' appeared historically as the phrase 'dread lock' or hyphenated 'dread-lock' in the 18th–19th centuries to describe matted hair; it later became the solid compound 'dreadlock' and the common plural 'dreadlocks' in modern English, especially after the 20th-century association with Rastafarian culture.

Initially, the components suggested 'a lock of hair that inspires dread (fear)' or simply a notable lock; over time the term shifted to a neutral descriptive name for a specific matted hairstyle and lost the primary sense of 'inspiring fear.'