Something aforesaid was stated or mentioned earlier — early enough for someone to remember. If you leave a tray of freshly baked cookies on the counter and announce to your family not to eat them yet, you'll be asking about the aforesaid cookies when ten of them are missing from the tray.
On a more serious note, the word aforesaid is often used in formal writing or legal documents. For example, an informational pamphlet about where to return items at the local library might say, "The aforesaid items must be returned to the front desk or the drop box by the due date." This word helps point back to something already discussed, making it clear which specific thing you are talking about. It’s useful for keeping communication clear and precise.