interjection

Okay, agreed, understood, or challenge accepted.

““Meet at eight.” “Bet.””

Thank you, goodbye, or a toast before drinking.

“Cheers for holding the door.”

Understood, acknowledged, or message received.

““The downtown train is skipping the stop.” “Heard.””

Really, understood, agreed, or that is true, depending on tone.

““That shop is open all night.” “Word?””