The online crowd-sourced dictionary UD (founded in 1999) allows anyone to submit definitions of words. A word may have multiple entries, and the most popular definitions are ranked highest in the list by users’ up- or down votes. The content of UD varies widely, from slang to proper nouns and from humorous to offensive. As a consequence, UD can be useful for recording new words or meanings which have not yet become attested, but it also contains an enormous amount of informal and often misguided content.
The UD entries are dominated by opinions, and the proportion of opinion-based definitions increases with frequency. This reflects the nature of the vocabulary in the database: many UD entries are slang words which capture specific local or informal usage, rather than general language trends. UD thus records new expressions which are rapidly adopted and used, but it does not necessarily represent the actual usage of these expressions.
For example, a search for the term’selfie’ on UD yields 353 entries, spanning a wide range of opinions and grammatical accuracy. These expressions include’selfie-conscious’ and’selfie-esteem’ as well as the slang terms’selfies,”selfied’ and ‘on fleek’ which all describe some aspect of the word selfie.
The large proportion of opinions in UD is one reason why it can be difficult to distinguish between real and fake words. However, UD can be helpful in determining the popularity of new slang, as shown by examining a plot of the frequency of the word in UD over time.