the egg or young form of a louse or other parasitic insec Meaning, pronunciation, example sentences, and more from Oxford Dictionaries. This Internet Slang page is designed to explain what the meaning of NIT is. The slang word / acronym / abbreviation NIT means . Internet Slang. A list of. Define nit: the egg of a louse or other parasitic insect also: the insect itself when young. Archaic words have a charm that never fades away, from French sounding to sushi ninja game mysterious ones. References in periodicals archive? SPUN 50 More Top Terms More from Dictionary, Thesaurus, and Translations. Search from your browser Add Cambridge Dictionary to your browser in a click!