Not written down
Contestants are not required to write down the words they give in letters rounds, or their solutions to numbers games. However, if both contestants give the same word or solution, the one who is asked second must prove that he/she actually discovered it and didn't just copy from the opponent.
Usually, this is done by checking the paper of the second contestant. For this reason, if one contestant hasn't written down the word or solution and there is a possibility of it matching the opponent's, he/she must state when declaring that it is not written down. Then, if both contestants declare the same length or number reached, the host will ask that contestant first.
If the second contestant to be asked for his/her word or solution has not written it down but had failed to declare this fact, a word or solution that matches that of the opponent is not accepted. On this wiki, words that were not scored for this reason are marked with NWD.