Why not delete both of them instead? Neither debug nor debugging give any useful information. In fact, they seem like prime examples of meta tags. For those who don't know, meta-tags are tags that
- Can’t work as the only tag on a question.
- Commonly mean different things to different people.
If I see a question tagged with debugging, what do I know? That the OP has a problem. Well yes, they wouldn't really be posting here otherwise. About 95.3% of all AU questions are about debugging something or other. What is this one about? Debugging hardware issues? A compilation error? A script? Someone's software? A dpkg issue?
The debug tag is not adding anything useful to the question and needs a helper tag in order to actually mean anything. So, forget synonyms, let's burn it with fire instead!