design: "Questions relating to software used for graphic design, web design, computer-aided design, et cetera." It appears to have been intended as a catch-all tag for software that didn't have a dedicated tag. However, each of the topics listed have had their own tags.
The tag creator got his wish with that "et cetera". The tag has 42 questions, all sharing the trait that the question relates to software that includes some kind of design function, or the body of the question includes the word design, or the OP knew somebody who once used the word "design" in a sentence.
On some of these, "design" might better go in a comment about the purpose for whatever the OP wants to do in the question, or as a complaint about the design of something not doing what they want. Some are "design" me a solution. I think I spotted one about doing something intentionally (by design).
After we clean up the tags that are just decoration or noise, there will probably be a few that are actually about some type of design software or the process of design. My opinion is that the tag is too meta to be useful. If it serves a function on a few questions, we probably have better tags to use instead.