Just now picked up this while surfing the net.

The word etymology ultimately comes from Greek etymon, meaning "the true sense of a word based upon its origin." It is related to eteos, meaning "true". It first appeared in English in 1398.

Entomology (1766) is from Greek entomon, meaning "insect", and that Greek word has an interesting background. It comes from Greek entemnein, meaning "to cut (a notch) into". Why would a notch-cutting word be applied to insects? Think of an ant, for example, and you'll picture the abrupt notches because the segments of its body.

Other terms have been coined to refer to the study of insects. They include insectology (1882) and bugology (1846).

Latin insectus is a calque for Greek entomos. Cf. AHD.