\Tre"mex\, n. [NL.] (Zo["o]l.)
A genus of large hymenopterous insects allied to the
sawflies. The female lays her eggs in holes which she bores
in the trunks of trees with her large and long ovipositor,
and the larva bores in the wood. See Illust. of {Horntail}.
Note: The pigeon tremex ({Tremex columba}), a common American
      species, infests the elm, pear, and other trees.