Failure to Elucidate

The definition is harder to understand than the term being defined.

Examples

Someone is lascivious if and only if he is wanton. (The term being defined is "lascivious". But the meaning of the term "wanton" is just as obscure as the term "lascivious". So this definition fails to elucidate.)
An object is beautiful if and only if it is aesthetically successful. (The term "aesthetically successful" is harder to understand than the term "beautiful".

Critique

Identify the term being defined. Identify the conditions in the definition. Show that the conditions are no more clearly defined than the term being defined.

Comment

On Political Obfuscation

"More than any other group ... politicians are criticized for the words they use. For example, Theodore Roosevelt disliked their use of weasel words, which are those words that someone uses to make a statement sound ambiguous. (In the same way that a weasel sucks the life out of an egg and leaves only the shell, a weasel word sucks the life out of the words around it.) ... Others have complained that pols use plastic words, words or phrases that normally have a specific meaning but are used by politicians to say whatever the audience wants to hear. Examples are "change" and "family values". (Paul McFedries, The Complete Idiot's Guide to a Smart Vocabulary (Penguin: 2001), p. 165.) The politician is trained in the art of inexactitude. His words tend to be blunt or rounded, because if they have a cutting edge they may later return to wound him. (Edward R. Murrow)