Even if you're dead certain you know the word, that's no reason not to participate.

You should
1) submit a fantastic daffynition to lure in the gullible and
2) vote for either
a) the right choice to demonstrate your knowledge (but don't say so until after eveyone else has voted) or
b) the cleverest daffynition to reward your colleague's subtlety...

...as the mood strikes you at the moment of selection!