(Impressive SPOILERs from Nick Baxter) In[111]:= DictionaryLookup[] // Length Out[111]= 92518 isn't as large as In[112]:= WordData[] // Length Out[112]= 149191 Yet it has In[132]:= Position[DictionaryLookup[], #] & /@ {"Cointreau", "cautioned", "auctioned"} Out[132]= {{{15133}}, {{12388}}, {{4816}}} In[134]:= WordDefinition /@ {"Cointreau", "cautioned", "auctioned"} Out[134]= {Missing[UnknownWord], {"warn strongly; put on guard"}, {"sell at an auction"}} Why doesn't WordData? In[133]:= Position[WordData[], #] & /@ {"Cointreau", "cautioned", "auctioned"} Out[133]= {{}, {}, {}} WordDefinition does not necessarily exclude say, proper names, even French disyllabic panvowels: In[130]:= WordDefinition@"Beauvoir" Out[130]= {"French feminist and existentialist and novelist (1908-1986)"} —rwg