The Spanish verb 'aceitar' (meaning 'to oil') comes from the Spanish noun 'aceite' ('oil') combined with the verbal suffix '-ar'. The noun 'aceite' has an interesting journey through Semitic languages - it comes from the Arabic word 'azzayt' meaning 'olive oil', which itself derives from the Aramaic 'zayta' also meaning 'olive oil'. This etymology reflects the historical influence of Arabic on Spanish vocabulary, particularly in terms related to agriculture and food products, due to the centuries-long Moorish presence in the Iberian Peninsula.

The most obvious related Spanish word is 'aceite' (oil), which is actually the base word from which 'aceitar' is derived. While 'aceite' is the noun referring to the substance itself, 'aceitar' is the action of applying or treating something with oil. You might also encounter 'aceitoso' (oily) and 'aceitera' (oil container or oil cruet), which are part of the same word family.

While there aren't direct English cognates from the same Aramaic/Arabic root, it's worth noting that English borrowed words related to olive oil through different routes. For example, the English word 'oil' comes from Latin 'oleum', which is ultimately related to Greek 'elaion', following a completely different etymological path from the Arabic-derived Spanish 'aceite' and 'aceitar'.