'seamster' originates from English, specifically formed from the word 'seam' (from Old English 'seam') combined with the agentive suffix '-ster' (from Old English '-estre'), where 'seam' meant 'seam, suture' and '-ster' marked an agent or person associated with an action.

'seamster' developed in Middle English as a compound of 'seam' and the agentive suffix (earlier forms like 'seamestre' or similar are attested in Middle English), and it eventually stabilized as the modern English word 'seamster'.

Initially, words with the suffix '-ster' often indicated a female worker, so the term could imply a female sewing worker; over time the gender implication weakened and 'seamster' came to mean simply 'a person who sews' (though the word itself became less common).