The Spanish word 'nunca' meaning 'never' comes from the Latin word 'numquam', which also meant 'never'. The Latin 'numquam' itself was formed by combining two words: 'ne' meaning 'not' and 'umquam' meaning 'ever'. So literally, the original Latin construction meant 'not ever', which naturally evolved to mean 'never'. Over time, as Latin evolved into Spanish, 'numquam' underwent phonetic changes to become the modern Spanish 'nunca', but kept its original meaning of 'never'.

While 'nunca' is already one of the most basic and common words in Spanish vocabulary, it's worth noting that it's often used in common phrases like 'nunca jamás' (never ever) where 'jamás' is another Spanish word for 'never' that comes from a different Latin root.

While English 'never' comes from a different root altogether, we can see a similar logical construction in English 'not ever' which parallels the original Latin formation of 'ne' (not) + 'umquam' (ever). This shows how different languages can arrive at similar expressions for the same concept through different etymological paths.