The scoring system of Dixonary is unsatisfactory in several respects.
Scores decline as more players play in a round. If there are only a few players it is "too easy".
Scores do not depend solely on the skill of the players, but also on the skill of the dealer: if a dealer chooses an easily-guessed word, players do well irrespective of the skill they display.
A companion paper to this, The Statistics of Dixonary Scoring, shows that these problems cannot be fixed simply by tinkering with the number of points awarded to a correct guess. A Lockstep Scoring System for Dixonary: a modest proposal explains how to deal with these problems properly.
Caution. The subtitle of this paper is a modest proposal. If the import of that phrase is not suggestive, Google for it before reading the document presented below.