from The American Heritage® Dictionary of the English Language, 4th Edition
- n. The middle of the three divisions of the thorax of an insect, bearing the middle pair of legs and the first pair of wings.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. The middle of the three segments of the thorax of an insect
from the GNU version of the Collaborative International Dictionary of English
- n. The middle segment of the thorax in insects. See Illust. of coleoptera.
from The Century Dictionary and Cyclopedia
- n. In entomology, the second or middle one of the three divisions of the thorax, situated between the prothorax and the metathorax, and bearing the second pair of legs and the first pair of wings. When very large, as in dipterous insects, it is simply called the thorax.
meso- + thorax (Wiktionary)