arrector

arrector /ar·rec·tor/ (ah-rek´tor) pl. arrecto´res   [L.] raising, or that which raises; an arrector muscle.

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ar·rec·tor (-rktr, -rk-)

n. pl. ar·rec·to·res (rk-tôrz)

See erector.

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arrector

pl. arrectores [L.] raising, or that which raises; an erector muscle.

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arrector pili muscle

smooth muscle that extends from the papillary zone of the dermis to the base of a hair follicle. Involuntary contraction causes hair erection which, in some species, is most noticeable on the neck and along the back (see hackles).