Webster’s Revised Unabridged Dictionary · 1913
Pleuron
Pleu′ron, n.; pl. Pleura (#). [NL., fr. Gr. πλευρόν a rib.] (Zoöl.) (a) One of the sides of an animal. (b) One of the lateral pieces of a somite of an insect. (c) One of lateral processes of a somite of a crustacean.