Malapropism (inappropriate use)

R.B Sheridan's play The Rivals (1775) has a character Mrs. Malaprop who to provide a humorous effect often misspeaks words like use of allegory for alligator and illiterate for obliterate. The character became so famous that it gave the word:
                   ' malapropism '
to us which means use of an incorrect word in place of a word with similar sound often creating comic effect.