Addendum

It was a long contract, but it wasn't complete. You had to add an "um" at the end.

The addendum you added was that the contract had to be signed by midnight on the 17th, or it was null and void. An addendum is markedly different from an amendment. Addendums usually tack on incremental terms, deadlines, and covenants, whereas amendments change pre-existing conditions for a deal to happen. Bottom line: caveat emptor.