'baetyl' originates from Greek, specifically the word 'baitylos' (βαιτύλος), possibly ultimately from a Semitic source; it entered classical languages as Latin 'baetylus'.

'baitylos' passed into Latin as 'baetylus' and later entered English as 'baetyl' (and occasionally 'baetylus').

Initially it meant 'a sacred stone (often believed to have fallen from the sky)'; this core meaning has largely been retained in modern usage, though the word is rare and mainly historical or literary.