What is i second that?

The phrase "I second that" is commonly used in conversational English to express agreement with something someone else has said. It's akin to saying, "I agree with that" or "I support that statement." This expression borrows from formal procedure, such as parliamentary or meeting protocols, where one person makes a proposal or motion, and another person must "second" it to show that at least two people support discussing or voting on the issue.

In a meeting or formal setting, "seconding" a motion typically means that the topic will then be open for discussion or will move forward to a vote. In everyday language, "I second that" is often used more informally to quickly express agreement or alignment in opinions or suggestions.