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n. The hindmost of the three divisions of the thorax of an insect, bearing the third pair of legs and the second pair of wings.

n. The hindmost of the three sections of the thorax of an insect

n. The last or posterior segment of the thorax in insects. See Illust. of coleoptera.

n. In entomology, the third and last segment of the thorax, succeeding the mesothorax, preceding the abdomen, and bearing the third pair of legs and the second pair of wings

"My first estimate of its size had been a little conservative; it was one of those fat moths with round thoraxes; the metathorax was especially round, looking like a witch's idea of a pot pie."

declivity of the metathorax   

coleoptera   

borax    mesothorax