rhinoceros beetle

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. Any of various large scarabaeid beetles of the genus Dynastes and related genera, characterized by horns on the head and thorax and found in tropical regions.

Century Dictionary and Cyclopedia

1. n. A beetle of the genus Dynastes, having in the male sex a large up-curved horn on the head, resembling somewhat the horn of the rhinoceros, as well as a more or less developed prothoracic horn. The common rhinoceros-beetle of the United States, Dynastes tityus, the largest of the North American beetles, has two large horns directed forward, one arising from the thorax and one from the head, in the male beetle only. The general color is greenish-gray with black markings. and between this form and a uniform brown there are many gradations. The larva feeds in decaying stumps and logs. Both beetle and larva have a peculiarly disagreeable odor, which, when they are present in any number, becomes insupportable. D. hercules of South America is another rhinoceros-beetle, specifically called the Hercules-beetle, whose prothoracic horn is immensely long. See also cut under Hercules-beetle.

Wiktionary

1. n. any of various tropical beetles, mostly of the genus Dynastes, having horns on the head and thorax; a pest on coconuts

GNU Webster's 1913

1. n. (Zoöl.) a very large beetle of the genus Dynastes, having a horn on the head.

WordNet 3.0

1. n. any of various large chiefly tropical beetles having horns on the head; pest on coconuts