Tit for tat is defined as a repayment of equal value for a trade or for retaliation.
(noun)An example of tit for tat is when you exchange four quarters for a dollar.
See tit for tat in Webster's New World College Dictionary
Origin: var. of earlier tip for tap (Fr tant pour tant): see tip
See tit for tat in American Heritage Dictionary 4
Origin:
Origin: Probably alteration of tip for tap
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