malapropism

Freudian slipと同様に言葉の滑稽な誤用（特に発音が似ている２語の混同）に"malapropism"があります。 Mrs. Malapropと言うそそっかしい婦人が度々似た言葉を誤って使ったことから名付けられたそうです。
A malapropism is so called after Mrs. Malaprop, a character noted for her amusing misuse of words in Richard Brinsley Sheridan's comedy The Rivals.
以下はhttp://www.fun-with-words.comからの抜粋です。　
Here are some of the original malapropisms from the lady herself: Mrs. Malaprop in Richard Sheridan's play The Rivals (1775).
In case you're not sure what it is that Mrs. Malaprop is intending to say we've put the correct word(s) in square brackets after each quotation.

"I have since laid Sir Anthony's preposition before her;"
[proposition]

"O, he will dissolve my mystery!"
[resolve]

"...she might reprehend the true meaning of what she is saying."
[comprehend]

日本語で喋っている時でもこのような経験は時々ありますね。