“Chalk it up” is a very old expression that goes back to the custom of writing a customer’s outstanding charges on a chalkboard, especially in a bar. Today it means to give credit in a more general sense, as in the expression “chalk it up to experience” (credit it to experience, add it to your account of experiences).” A successful team may chalk up another win.
You chock a vehicle parked on a slope by slipping a wedge called a “chock” behind its wheels.
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