'fervent' originates from Latin, specifically the word 'ferventem,' where 'fervēre' meant 'to boil or glow.'

'ferventem' transformed into the Old French word 'fervent,' and eventually became the modern English word 'fervent' through Middle English.

Initially, it meant 'to boil or glow,' but over time it evolved into its current meaning of 'having passionate intensity.'