The Spanish word 'factor' comes from the Latin word 'factor' meaning 'maker' or 'doer'. This Latin word was formed by combining the supine form 'factum' (meaning 'something done') of the verb 'facere' ('to do, to make') with the agent suffix '-tor', which indicates someone who performs an action. Over time, the meaning evolved from someone who 'makes' or 'does' things to its modern meaning of an element or circumstance that contributes to a result.

Several common Spanish words share this Latin root 'facere'. Some examples include: 'hacer' (to do/make), 'fácil' (easy, literally 'doable'), 'hecho' (fact/deed, from Latin 'factum'), and 'fábrica' (factory, a place where things are made). All these words maintain a connection to the basic concept of 'making' or 'doing'.

Many English words are related to 'factor' through the same Latin root 'facere'. Some familiar examples include 'factory' (a place where things are made), 'fact' (something that was done or made to be true), 'facile' (easy to do), and 'manufacture' (literally 'to make by hand'). The English word 'factor' itself shares the same Latin origin and parallel meaning with its Spanish cousin.