The Spanish word 'aceituna' (meaning 'olive') has an interesting journey through Semitic languages before entering Spanish. It began with the Aramaic word 'zayta' meaning 'olive'. This was modified to 'zaytuna' (meaning 'little olive') in Aramaic, which then passed into Classical Arabic as 'zaytunah'. The word then evolved in Andalusi Arabic (the Arabic dialect spoken in medieval Islamic Spain) to 'azzaytúna', before finally entering Spanish as 'aceituna'. The transformation from the Arabic 'az-' prefix to Spanish 'ac-' is a common pattern seen in Spanish words borrowed from Arabic.

A closely related and common Spanish word is 'aceite' meaning 'oil', particularly olive oil. Both 'aceituna' and 'aceite' share the same Arabic roots related to olives. While 'aceituna' refers to the fruit itself, 'aceite' refers to the oil extracted from it. Another related word is 'aceitunero/a', which means 'olive picker' or someone who works with olives.

While English doesn't have any direct cognates from this Arabic/Aramaic root, it's worth noting that many English words related to olives come from Latin 'oliva'. However, English has borrowed some words through Spanish and Arabic channels that are ultimately related to 'aceituna', such as 'azulejo' (decorative tile), which got its name because early Spanish tiles often had a blue color produced using oil-based glazes.