Dear Word Detective: A recent internet exchange where somebody was pegged as a “nit-picker” for pointing out errors in grammar and usage produced this post: “In terms of the phrase ‘nitpicking,’ a ‘nit’ is a small ball of cloth that is produced by yarn in things like sweaters and such. Nitpickers were the people who removed such things from the garment so that it had a smooth appearance, and as such, were required to be very exacting and detail-oriented. This is where the term in common use came from.” The previous discussion had all been about “nits” as in small insects or larvae and primate grooming behavior, which strikes me as a much more likely origin for the term. The post quoted above strikes me as more like folk etymology than a probable explanation. — Joe.
Gosh, that sounds like a great job. Is that something I could do at home while I watch TV? I’m very detail-oriented, as long as the details are simple and don’t involve numbers. I’ve tried those envelope-stuffing gigs, but I seem to wind up with pretty serious paper cuts and the cats always steal the stamps.
You’re absolutely correct in your suspicion that the explanation of “nitpicker” you read is off-base. It sounds, as a matter of fact, like something invented by someone (not necessarily the person who posted it) who knew the truth, but chose to “sanitize” the origin of the term to avoid offending people who might be disturbed by a discussion of “nits.” But hey, “disturbing” is our middle name around here.
A “nit” is the egg (or larva) of a louse, especially the common head louse that has plagued humans throughout our species’ history. Nits having been a constant feature of human society for so long, the word itself is very old, going back to an Indo-European root, and most European languages have a word closely related to our English “nit.”
Nits are very tiny things, and thus, as you mention, most primates depend on family and friends to pick them off their pelts. Humans now have fine combs for this, but for much of history it helped to have someone who would undertake the cleaning.
“Nit” has been used to mean an insignificant or foolish person since the 16th century (“Thou Flea, thou Nit, thou winter cricket thou,” Shakespeare, 1616), but “nitwit,” meaning a very stupid person, is a fairly recent invention, dating only to 1914. Surprisingly, although people have been picking nits off of each other for centuries, “nitpicker” is even more recent, first appearing in the early 1950s in the sense of someone who finds and complains about the smallest flaws.
Interestingly, “nitpicker” has apparently never been used in a literal sense to mean someone who finds and removes nits, only in the “overzealous critic” sense.


On the History Channel there is a show called “The Worst Jobs in History”. The host was told that a nit picker was someone that picked nits out of the wigs of well-to-do people.
http://www.channel4.com/history/microsites/W/worstjobs/stuart.html#5