'aspergillus' originates from Neo-Latin/Latin, specifically the Latin word 'aspergillum' (a small sprinkler), ultimately from Latin 'aspergere' meaning 'to sprinkle'.

'aspergillum' (Latin, a little sprinkler) was adopted into Neo-Latin/botanical Latin as the genus name 'Aspergillus' (because the conidiophore resembled a small brush or sprinkler), and this became the modern English scientific name 'Aspergillus' and its plural forms such as 'aspergilli'.

Initially it referred to a small sprinkler or brush; over time the term was applied (by analogy) to this group of fungi and now denotes the fungal genus 'Aspergillus' (with 'aspergilli' used as a plural).