A mite or tick; a member of the Acari order of arachnids that includes dust mites and parasitic mites.
From Greek akari (tiny creature). Used as both a common name and scientific designation since the 1600s when microscopy revealed these previously invisible animals.
The word acarus was coined before people could actually see mites clearly—it literally just means 'tiny creature,' which is hilariously vague given that we now know there are millions of different mite species!
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