'lugworm' originates from English, specifically the compound 'lug' + 'worm', where 'lug' was a dialect term (sense uncertain) and 'worm' meant 'worm'.

'lugworm' developed in English by compounding dialect 'lug' with Old English 'wyrm' (worm), and the form stabilized as 'lugworm' in modern English; the common species is placed in the scientific genus 'Arenicola' (from Latin).

Initially the name referred to a particular kind of worm (with an uncertain origin for 'lug'); over time it became the common name for the sand-dwelling polychaete (Arenicola) widely used as bait.