'knot' originates from Old English, specifically the word 'cnotta', where the root meant 'a knot, lump or fastening'.

'knot' changed from Old English word 'cnotta', which in turn reflects Proto-Germanic forms such as '*knutt-'/*'*knot-'; over time the form simplified into the modern English 'knot'.

Initially it meant 'a knot or lump' (a physical fastening), but over time the sense broadened to include the verb 'to tie' and figurative senses (e.g., a problem or difficulty, a cluster or tangle).