a. Any of numerous arthropod animals of the class Insecta, having an adult stage characterized by three pairs of legs and a body segmented into head, thorax, and abdomen and usually having one or two pairs of wings. Insects include the flies, crickets, mosquitoes, beetles, butterflies, and bees.
b. Any of various other small, chiefly arthropod animals, such as spiders, centipedes, or ticks, usually having many legs. Not in scientific use.
2. An insignificant or contemptible person.
[Latin īnsectum, from neuter past participle of īnsecāre, to cut up (translation of Greek entomon, segmented, cut up, insect) : in-, in; see IN-2 + secāre, to cut; see sek- in the Appendix of Indo-European roots.]
in′sec·tival (ĭn′sĕk-tīvəl) adj.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.