What is the general procedure for deleting or merging tags that are duplicates/synonyms of other tags?
As I understand, unused tags will get deleted automatically after a period of time.
Where tags should be merged, is there a process where the less established tags get migrated over to the more established tag?
See What are tag synonyms and merged tags? How do they work?
Users with more than 1250 reputation and a total answer score of 5 or more on the tag, can suggest tag synonyms. Users with a total answer score (total upvotes minus total downvotes) of 5 or more on the tag, can vote for tag synonyms. Suggestions will be automatically approved when they reach a score of 4, and automatically deleted when they reach a score of -2.
Moderators can merge synonyms into the parent tag.
Although this question is answered I found this post on meta.stackoverflow that is also useful. (Credit to Kedarnath)
One way to remove tag is just remove the duplicate tag from all the tagged question (and even replace it with the appropriate tag). After 24 hours all non-used zombie tags get deleted by system.
How can we get rid of misspelled and unused (or “zombie”) tags?
Another way is to post the question on meta and request for the particular tag to be merged or deleted. Moderator/developer will merge/remove it.
