'neutrophil-mediated' is a modern English compound combining 'neutrophil' (from New Latin 'neutrophilus', ultimately from Greek elements meaning 'neutral' + 'loving') and 'mediated' (from Latin 'mediatus', past participle of 'mediare', related to 'medius' meaning 'middle').

'neutrophil' developed in biomedical New Latin in the 19th century from Greek/Latin roots referring to staining affinity (neutral + -phil), while 'mediate' comes from Latin 'mediare/mediatus'; in modern English these elements combined to form the compound adjective 'neutrophil-mediated'.

Originally 'mediate' meant 'to place in the middle' or 'act as an intermediary'; over time it came to mean 'to cause or convey an effect through an agent', so 'neutrophil-mediated' now means 'caused by or occurring via neutrophils'.