**[Done](https://mathoverflow.net/posts/233412/revisions)**

I propose to deprecate [tag:abstract-algebra]. It seems redundant with other tags, very broad, and the usage seems inconsistent. 

I feel it is comparable to the meanwhile removed [tag:topology] and the deprecated [tag:geometry].

(Explication on terminology: To deprecate a tag is not a technical measure. What it means is that the tag-description is changed to say this tag should no longer be used. Over time it could then be slowly phased out via retagging.)