The Spanish word 'permiso' (meaning 'permission') comes from the Latin word 'permissum', which also meant 'permission'. The Latin word was formed by combining two elements: the prefix 'per-' meaning 'through' or 'completely', and 'missum' meaning 'sent'. When these elements combined, they created the concept of something being 'sent through' or 'allowed to pass through', which evolved into the meaning of 'permission' that we know today.

Some related Spanish words include 'permitir' (to permit/allow), which shares the same Latin roots. Another related word is 'mensaje' (message), which comes from the same Latin root 'missum' (sent), showing how the concept of 'sending' is preserved in modern Spanish vocabulary.

English speakers can easily connect 'permiso' to several familiar English words. 'Permission' and 'permit' are direct cognates that share the same Latin ancestry. The 'mis-' element from 'missum' (sent) appears in many English words related to sending, such as 'mission', 'missile', and 'message'. The prefix 'per-' is also found in many English words like 'perfect' (completely done) and 'persist' (thoroughly continuing).