'avidous' originates from Latin, specifically the word 'avidus', where 'avid-' meant 'eager, greedy'.

'avidous' was formed in English by combining the Latin-derived root 'avid-' (via the adjective 'avid') with the English adjectival suffix '-ous', producing 'avidous' as an adjective meaning 'having eagerness or greed'.

Initially, the root meant 'eager' or 'greedy' in Latin; in English the word 'avidous' (rare/archaic) retains the sense of 'having a strong desire', sometimes emphasizing greediness.