Acaroid means resembling a mite or a tick. A mite is a
type of small insect that does not have a
backbone/spine, but has an external skeleton, a body
divided into segments, and jointed attachments to the
body. Ticks are another type of small insect without a
backbone/spine and with jointed legs. Mites and ticks
are classified in a scientific subclass known as
Acarina. Both of these insects are known to cause
harm to humans but mites usually affect humans by
being inhaled in bedding or in the air (e.g., dust mites)
whereas ticks usually affect humans by biting them in
the wilderness (e.g., the woods).
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One type of insect, known as the harvestman (which some people refer to as a “daddy
longlegs”), actually resembles mites more than spiders from a scientific classification
perspective. Some mites are referred to as acaroid mites even though that is really
saying the same thing twice (i.e., a mite that looks like a mite). Some cells are described
as acaroid because they resemble a mite in appearance under a microscope.

Acaroid comes from the Greek word “akari” meaning “mite” and the Greek word “eidos”
meaning “resemblance.” Put the words together and you have “mite resemblance.”

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