'abstentious' originates from Latin, specifically the word 'abstinentia,' where 'ab-' meant 'away from' and 'tenere' meant 'to hold.'

'abstinentia' transformed into the English word 'abstention,' and eventually became the modern English word 'abstentious.'

Initially, it meant 'holding oneself away from indulgence,' and this meaning has largely remained the same in modern usage.