In his August 1977 Word Ways article on words ending in -onym, George Scheetz asked readers if they could identify contronym or charactonym, neither of which appears in standard dictionaries. The former word was apparently coined by Jack Herring, who defined it as a word which can be used in two contradictory senses.
Word Ways: Vol. 11
, Article 10.
Available at: http://digitalcommons.butler.edu/wordways/vol11/iss1/10