Tit-for-tat means doing something bad to someone because they have done something bad to you. Synonyms: an eye for an eye, blow for blow, retaliation.

For example, a CNN news story states that Donald Trump’s tit-for-tat philosophy on tariffs is not quite what it seems.

When several countries expelled Russian diplomats, Putin went tit for tat.

I noticed she didn’t send me a card- I think it was tit for tat because I forgot her birthday last year.

Tradução: em represália, na mesma moeda, retaliação, olho por olho.