The Spanish word 'decorativo' (meaning 'decorative') traces back to the Latin word 'decus', which meant 'ornament' or 'dignity'. From this root, the Latin verb 'decorare' ('to decorate') was formed, which then gave us the past participle 'decoratus' ('decorated'). This evolved into the Spanish verb 'decorar' ('to decorate'). The modern Spanish adjective 'decorativo' was formed by adding the adjective suffix '-ivo' to the stem of 'decorar', creating a word that describes something that serves to decorate or embellish.

Some simpler and more common Spanish words that share this etymology include 'decorar' (to decorate), 'decoración' (decoration), and 'decorado' (decorated/decor). These all come from the same Latin root and maintain the basic meaning of adorning or embellishing something.

English speakers will recognize many cognates from this word family, including 'decorate', 'decoration', 'decorative', and even 'decorous' (meaning well-behaved or proper, reflecting the 'dignity' sense of the original Latin 'decus'). These English words share the same Latin ancestry as the Spanish 'decorativo' and have maintained very similar meanings, making them easy to remember for English speakers learning Spanish.