'low-set' originates from English, combining the adjective 'low' and the verb/adjective 'set', where 'low' meant 'not high / near the ground' and 'set' meant 'to place or fix in position'.

'low' developed from Old English words (e.g. 'hlāw' meaning a mound, later coming to mean 'not high') and 'set' comes from Old English 'settan' meaning 'to cause to sit or place'; the compound 'low-set' formed in Modern English as a descriptive compound adjective.

Initially, 'low' referred broadly to being near the ground (and 'set' to being placed); over time the compound 'low-set' came to be used specifically to describe features positioned lower than typical (for example, low-set ears).