from The American Heritage® Dictionary of the English Language, 4th Edition
- n. A retort accusing an accuser of a similar offense or similar behavior.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. An argument whereby an accusation or insult is turned back on the accuser.
from The Century Dictionary and Cyclopedia
- n. A retort consisting of a charge or accusation similar to that which has been made by one's antagonist, as in the case of a person charged with bribery who replies that his accuser's hands are not clean of corruption: also used attributively: as, the tu quoque argument is not conclusive.
Latin tū quoque, you also : tū, you + quoque, also.(American Heritage® Dictionary of the English Language, Fourth Edition)
From Latin tu ("you") quoque ("also") (Wiktionary)