affidavit

af-uh-DAY-vit

meaning in plain English

A written promise that you swear is true, signed in front of someone who can make sure you’re telling the truth.

for example

She sent in her affidavit instead of going to the meeting to speak for herself.

An affidavit is like a written promise where you say, ‘This is the truth,’ and someone official watches you sign it. Think of it like signing a letter that says, ‘I promise this is real,’ but it’s serious enough to be used in real situations.