'denitrifier' originates from French and English roots, specifically from the word 'denitrify' plus the agent suffix '-er', where 'denitrify' means 'to remove nitrogen or nitrogen compounds'.

'denitrify' was formed in English from the prefix 'de-' (removal) and 'nitrify' (to combine or treat with nitrogen), and the agent noun '-er' was added to form 'denitrifier'.

Initially, it meant 'one that denitrifies', and this meaning has remained consistent, referring to organisms that perform denitrification.