'sapid' originates from Latin, specifically the word 'sapidus', where 'sapere' meant 'to taste; to have flavor'.

'sapid' came into English via post-medieval scholarly/borrowing use of Latin 'sapidus' (from Classical Latin) and was adopted into English vocabulary in the modern period as the adjective 'sapid'.

Initially it meant 'tasty, full of flavor' in Latin, and it kept that sense in English; it has also acquired a figurative sense of 'pleasing or interesting' over time.