The Spanish word 'marrana' (meaning 'female pig' or 'beam') has an interesting etymology that traces back to Classical Arabic. It comes from the Arabic word 'muḥarram' meaning 'forbidden or declared anathema', which evolved into the Andalusi Arabic 'maharram' ('forbidden'). This term became 'marrano' in Spanish, initially referring to a pig or a beam at the bottom of a well, and then developed the feminine form 'marrana'.

The semantic shift from 'forbidden' to 'pig' likely occurred because pork was forbidden (muḥarram) in both Islamic and Jewish dietary laws. The term may have originally been used pejoratively to refer to converted Jews or Muslims who were suspected of secretly maintaining their old religious practices, before eventually coming to simply mean 'pig' in standard Spanish usage. The secondary meaning of 'beam' likely developed from the pig's cylindrical body shape.

The masculine form 'marrano' is closely related to 'marrana' and is more commonly used. Both words can refer to either pigs or beams, with 'marrano' being the male pig and 'marrana' being the female pig.

While there aren't any common English words directly related to 'marrana', English has borrowed the term 'marrano' as a historical term specifically referring to Spanish Jews who converted to Christianity while secretly maintaining Jewish practices. This preserves more of the original Arabic meaning of 'forbidden' rather than the modern Spanish meaning of 'pig'.