An unpaired word is one that, according to the usual rules of the language, would appear to have a related word but does not. Such words usually have a prefix or suffix that would imply that there is an antonym, with the prefix or suffix being absent or opposite.

Many unpaired words are the result of one of the words disappearing from popular usage, though others were never part of a pairing and just begin with the same letters as used in common prefixes.

Unpaired words in English

Prefixes

Word	Paired word(s)	Notes
Disambiguate	*Ambiguate	Not a word; derived from dis- + ambigu(ous) + -ate in the mid-20th century
Disconsolate	Consolate	Derived from the Latin consolatus; rarely used
Disheveled, Dishevelled	*Sheveled, *Shevelled	Not a word; from the Old French deschevelé
Indomitable	Domitable	Rarely used antonym
Ineffable	Effable	Rarely used antonym
Innocent	Nocent	Not an exact antonym; rarely used
Innocuous	Nocuous	Rarely used antonym
Uncouth	Couth	Derived from Old English word cunnan meaning "well-known" or "familiar"; rarely used
Ungainly	Gainly	Rarely used antonym
Unkempt	Kempt	Rarely used antonym
Unruly	Ruly	Rarely used antonym
Unstinting	Stinting	Rarely used antonym
Untoward	Toward	Not an antonym
Unwieldy	Wieldy	Rarely used antonym

Humorous unpaired words

The quote "if con- is the opposite of pro-, is congress the opposite of progress?" is not attributed to any individual but is frequently repeated, being mentioned by Forbes magazine amongst others. Congress is from the Middle English congresse meaning a body of attendants, (Latin congressus, meaning a meeting), and progress is from Middle English progresse (Latin prōgressus) meaning to advance. Here, pro and con are in fact not opposite, with con meaning "together" and pro meaning "supporting" or "in place of" (while in other contexts con, or contr- can mean "against").

See also

References

• " Unpaired words" at World Wide Words
• " Absent antonyms" at 2Wheels: The Return