The Spanish word 'labios' (meaning 'lips') comes directly from the Latin word 'labium', meaning 'lip'. The word underwent minimal changes as it evolved from Latin to Spanish, with the main difference being that 'labios' is the plural form, while 'labio' is the singular form in Spanish.

The singular form 'labio' is naturally related and commonly used in Spanish. You might also encounter words like 'labial' (relating to the lips) in Spanish, which comes from the same Latin root.

Several English words share the same Latin root 'labium'. These include 'labial' (relating to the lips), as in 'labial consonants' which are sounds made with the lips. The scientific term 'labium' is still used in English, particularly in anatomy and biology. The word 'labiodental' (involving both lips and teeth) is another related term that English speakers might recognize.