There already exists a feature to make certain tags synonyms of each other. For example, on Gardening & Landscaping, we have
dionaea as a synonym of
venus-fly-trap so that users who search by the common name or the genus will be presented with the same result
In order to do this, you should suggest a synonym and get 4 other users to vote on it (also requires you to have a minimum rep on the site—1.25k on beta and 2.5k on others, if I remember right—and a minimum rep in the particular tag). Needless to say, not many users can satisfy these conditions, and just give up on suggesting.
Mods can also create synonyms regardless of rep on site/tag and without community votes. However, unless it is an obvious one (e.g., on gardening, all tags are plurals, so singular->plural is done immediately), you might not want the mod to make synonyms as they wish.
You have two possible options here:
- Suggest a synonym and ask users to vote in chat — this gets some eyes on the issue.
- Open a meta post suggesting possible synonyms. Rather than creating a post for each request, it might be better to have a single question where users can suggest synonyms in the answers and mods can create after community feedback. Once set, the answer can be deleted to keep the slate clean. Here is how we do it on gardening. There are quite a few deleted answers on that page, and now we've switched to doing it through revisions.
Once you raise a meta post, if users agree, they themselves can suggest synonyms (if you don't have rep) and either other users or mods can approve, thereby netting you a "Synonymizer" badge.