The Spanish word 'motivo' (meaning 'motive' or 'reason') comes from the Latin word 'motivus', which meant 'relating to movement'. The Latin 'motivus' itself was formed by combining two parts: the verb 'movere' (meaning 'to move') and the suffix '-ivus' (meaning 'relating to'). This combination created a word that literally meant 'relating to movement', which evolved to describe the reason or force that 'moves' someone to act in a certain way.

Several common Spanish words share this same Latin root 'movere': 'mover' (to move), 'movimiento' (movement), 'móvil' (mobile), and 'moción' (motion). You can see how all these words relate to the concept of movement, while 'motivo' specifically evolved to describe what moves or motivates someone to do something.

Many English words are related to 'motivo' through the same Latin root 'movere': 'motive', 'motion', 'move', 'movement', 'motor', and 'motivate'. The connection is clear when you think about how a motive is something that 'moves' you to action. The English word 'motive' is particularly close to the Spanish 'motivo', both in meaning and form, as they share the same Latin ancestor 'motivus'.