The Spanish word 'sentimental' comes from the Latin verb 'sentire' meaning 'to feel or perceive'. This evolved into the Spanish verb 'sentir' ('to feel'). The noun 'sentimiento' ('feeling') was formed by adding the suffix '-miento' (which creates nouns indicating an action or its result) to 'sentir'. Finally, the adjective 'sentimental' was created by adding the suffix '-al' (meaning 'relating to') to 'sentimiento', thus meaning 'relating to feelings' or 'emotional'.

Some simpler and more common Spanish words that share this etymology include the basic verb 'sentir' (to feel), 'sentido' (sense), and 'sentimiento' (feeling). These all preserve the core meaning of experiencing or perceiving emotions or sensations from the Latin root.

The English words 'sentiment', 'sentimental', and 'sense' are closely related, all deriving from the same Latin root 'sentire'. The English 'sentimental' is particularly close to the Spanish word, as both languages borrowed and adapted this word formation in similar ways. The English word 'sense' and its derivatives like 'sensible' and 'sensitive' also share this ancient root, though they've evolved to cover both emotional and physical perception.