An Introduction to Obsolete Words

Obsolete word is a temporal label commonly used by lexicographers (that is, editors of dictionaries) to indicate that a word (or a particular form or sense of a word) is no longer in active use in speech and writing.

"In general," notes Peter Meltzer, "the difference between an obsolete word and an archaic word is that, although both have fallen into disuse, an obsolete word has done so more recently" (The Thinker's Thesaurus, 2010).

The editors of The American Heritage Dictionary of the English Language (2006) make this distinction:

Archaic. [T]his label is attached to entry words and senses for which there is only sporadic evidence in print after 1755 . . ..
Obsolete. [T]his label is attached to entry words and senses for which there is little or no printed evidence since 1755.

In addition, as Knud Sørensen points out, "it sometimes occurs that words which have become obsolete in Britain continue to be current in the United States (compare Amer. Engl. fall and Brit. Engl. autumn)" (Languages in Contact and Contrast, 1991).

Following are some examples of obsolete words:

Illecebrous

"Illecebrous [ill-less-uh-brus] an obsolete word meaning 'attractive, alluring.' From a Latin word meaning 'to entice.'"
(Erin McKean, Totally Weird and Wonderful Words. Oxford University Press, 2006)

Mawk

"The underlying meaning of mawkish is 'maggotish.' It was derived from a now obsolete word mawk, which meant literally 'maggot' but was used figuratively (like maggot itself) for a 'whim' or 'fastidious fancy.' Hence mawkish originally meant 'nauseated, as if repelled by something one is too fastidious to eat.' In the 18th century the notion of 'sickness' or 'sickliness' produced the present-day sense 'over-sentimental.'"
(John Ayto, Word Origins, 2nd ed. A & C Black, 2005)

Muckrake

"Mudslinging and muckraking--two words commonly connected with the pursuit of an elected office and the flotsam the campaigns leave in their wake.
"Voters seem fairly familiar with the term used to describe malicious or scandalous attacks against opponents, but the latter 'm' word may be new for some people. It is an obsolete word describing a tool used to rake muck or dung and used in reference to a character in John Bunyan’s classic Pilgrim’s Progress [1678]--'the Man with the Muck-rake' who rejected salvation to focus on filth."
(Vanessa Curry, "Don’t Muck It Up, and We Won’t Rake It." The Daily Herald [Columbia, TN], April 3, 2014)|

Slubberdegullion

Slubberdegullion is "n: a slobbering or dirty fellow, a worthless sloven," 1610s, from slubber "to daub, smear, behave carelessly or negligently" (1520s), probably from Dutch or Low German (cf. slobber (v)). Second element appears to be an attempt to imitate French; or perhaps it is French, related to Old French goalon "a sloven." "Century Dictionary speculates the -de- means 'insignificant' or else is from hobbledehoy."

Snoutfair

Snoutfair is a person with a handsome countenance (literally, a fair snout). Its origins are from the 1500s.

Lunting

Lunting means to walk while smoking a pipe. Lunting is also the emantion of smoke or steam from a tobacco pipe, or the flame used to light a fire, torch, or pipe, The word lunting originated in the 1500s "from either the Dutch word 'lont' meaning a slow match or fuse or the Middle Low German 'lonte' meaning a wick.

With Squirrel

With squirrel is a euphemism that means pregnant. It originated in the Ozark Mountains in the early 20th century.

Curglaff

Curglaff is commonly felt by people in northern climes —it is the shock that one feels when first plunging into cold water. The word curglaff originated from Scotland in the 1800s. (Also spelled curgloff).

Groak

To groak (verb) is to watch someone longingly while they are eating, in the hope that they will give you some of their food. The origin is possibly Scottish. 

Cockalorum

Cockalorum is a little man who has an over-inflated opinion of himself and thinks himself more important than he is; also, boastful speech. The origin of cockalorum may be from the from the obsolete Flemish word kockeloeren of the 1700s, meaning "to crow."