The Spanish adverb 'profundamente' (meaning 'deeply') comes from combining the adjective 'profundo' ('deep') with the adverbial suffix '-mente' (meaning 'in a manner of'). The suffix '-mente' itself comes from the Latin word 'mens' meaning 'mind'.

The adjective 'profundo' traces back to Latin 'profundus' meaning 'deep', which was formed by combining the prefix 'pro-' ('forward') with 'fundus' ('bottom, foundation'). The literal sense was thus 'moving forward toward the bottom' or 'far down', which developed into the general meaning of 'deep'.

Some related Spanish words that might be easier to remember include the adjective 'profundo' itself, which directly means 'deep' and is used both literally (as in 'un lago profundo' - 'a deep lake') and figuratively (as in 'un pensamiento profundo' - 'a deep thought'). The suffix '-mente' appears in many common Spanish adverbs like 'normalmente' (normally), 'rápidamente' (rapidly), and 'finalmente' (finally).

English speakers might recognize the connection to words like 'profound', which comes from the same Latin root 'profundus'. While 'profound' in English tends to emphasize deep intellectual or emotional depth rather than physical depth, you can see how both meanings evolved from the idea of 'going to the bottom of something'. The English word 'foundation' is related to the Latin 'fundus' that forms part of this word. Additionally, the Latin 'mens' (mind) that gave us '-mente' is related to English words like 'mental' and 'mentality'.