The Spanish word 'viaje' (meaning 'journey' or 'trip') can be traced back to the Latin word 'via', which meant 'road' or 'way'. From 'via', the Latin language derived 'viaticum', which referred to 'provisions for a journey' - essentially the supplies and necessities one would need while traveling on the road. This word evolved into the Catalan 'viatge' meaning 'journey', which was then borrowed into Spanish as 'viaje', maintaining the same meaning.

Several common Spanish words share this same Latin root 'via': 'vía' means 'way' or 'route', 'viaducto' means 'viaduct' (a bridge-like structure), and 'desviar' means 'to deviate' or 'to divert'. All these words maintain a connection to the concept of paths, roads, or movement along a route.

English speakers might recognize this same Latin root 'via' in several familiar words: 'via' itself is used in English to mean 'by way of' or 'through'. Other related English words include 'viaduct' (a bridge-like structure for roads), 'deviate' (to move away from a path), and even 'trivial' (which originally meant 'where three roads meet'). The word 'voyage', while similar in meaning to 'viaje', comes from the same Latin root.