A tag called "phrase-origin" has recently been created in this question, a kind of question that up till now has been labelled "etymology" according to our tag description. It has been argued that the term "etymology" is used for single words, whereas for the history and origins of a phrase the suitable label should be "phrase-origin". If it's that way, we sould modify the description of the tag "etymology" and retag lots of questions that at this moment are labeled "etymology", for instance, this one.
On the other hand, other language StackExchange sites, such as ELU, have a short descrption of the tag "etymology" very similar to the one we have and use it to label lots of questions asking about the origin of a phrase or expression such as, for instance, this question.
Update:
However, as @Gio has pointed out, the tag "phrase-origin" also exists on ELU, but without any tag description, and some questions are labeled with this tag, which seems a little bit incoherent. And, as @egreg has said, to increase the confusion, «the long description of "etymology" on ELU only refers to single words, and phrases only appears in the short description and in the last paragraph. No explanation on how phrases can be considered is provided.»
What do you think we should do about this?