Back Formation

Here's an interesting concept I just learned about: back formation. Back formation occurs when a word is mistakenly assumed to have come from a particular root. That "root" is then actually coined as a word.

Burgle, for example, was assumed to be the root of the word burglar, and has recently been recognized by dictionary-makers as a synonym for burglarize. Burglar, however, predates burgle.

Couth is another example--sort of. It has been used for some time as a facetious synonym for manners. I always found it humorous that one could be uncouth, but not merely couth. I read today, however, in David Feldman's book, Who Put the Butter in Butterfly?, that uncouth is rooted in the Old English word couth, which meant "known," or "familiar." Uncouth took on negative connotations as it applied to the manners or behaviors of outsiders. Uncouth in that pejorative sense survived into modern English, but not its root, couth. The reemergence of couth, now recognized in several dictionaries, is from the evolved definition of uncouth (boorish, unmannerly).

So, the couth that spawned uncouth is not the same as the couth we unwittingly invented. Get it?

Anyway, some other examples of back-formations (courtesy Wikipedia) include:

automate (from automation)
aviate (from aviator)
bartend (from bartender)
book-keep (from book-keeping)
brainwash (from brainwashing)
bulldoze (from bulldozer)
bus (from busboy)
choreograph (from choreography)
creep (from creepy)
destruct (from destruction)
donate (from donation)
edit (from editor)
escalate (from escalator)
emote (from emotion)
funk (from funky)
grovel (from groveling)
haze (from hazy)
isolate (from isolated)
legislate (from legislator)
manipulate (from manipulation)
opine (from opinion)
proofread (from proofreader)
spectate (from spectator)
tase (from taser)
upholster (from upholstery)