Noah Webster's New International Dictionary of the English Language

1. (n.) One of the Insecta; esp., one of the Hexapoda. See Insecta.

2. (n.) Any air-breathing arthropod, as a spider or scorpion.

3. (n.) Any small crustacean. In a wider sense, the word is often loosely applied to various small invertebrates.

4. (n.) Fig.: Any small, trivial, or contemptible person or thing.

5. (a.) of or pertaining to an insect or insects.

6. (a.) Like an insect; small; mean; ephemeral.