'ansioso' originates from Latin, specifically the word 'anxiosus', where the root 'anxius' ultimately relates to Latin 'angere' meaning 'to strangle' or 'to cause distress'.

'ansioso' changed from the Latin word 'anxiosus' through Late Latin and Old Spanish into the modern Spanish word 'ansioso'.

Initially, it meant 'full of anxiety or distress', and over time it also acquired the related sense of 'eager' or 'impatient' in contexts of desire or anticipation.