Webster's Revised Unabridged Dictionary · 1913

Pleuron

Pleuron , noun

[New Latin, from Greek {not transcribed} a rib.]

(a)
(Zoology) One of the sides of an animal.
(b)
(Zoology) One of the lateral pieces of a somite of an insect.
(c)
(Zoology) One of lateral processes of a somite of a crustacean.