What is the meaning of Insect?

An arthropod (in the Insecta class) characterized by six legs, up to four wings, and a chitinous exoskeleton.

Any small arthropod similar to an insect, including spiders, centipedes, millipedes, etc.

A contemptible or powerless person.

insect, arthropod of the class Insecta

bug (any small arthropod or invertebrate that somewhat resembles an insect)

Source: wiktionary.org