We have two tags, space-sickness and motion-sickness on the main site, in the context of Space Exploration both describing same range of symptoms known as space adaptation syndrome a.k.a. space motion sickness.
Any objections to making these two tag synonyms? I felt I had to reject one suggested edit including the other tag on top of the first one, and would like your input, if my rejection was warranted and the suggested edit was needlessly duplicating two of the same (i.e. we can merge two tags as synonyms), or do I need to apologize to the editor for failing to see some major difference in definition of the two tags in question? What is the suggested course of action when two or more tags are possible synonyms (thus this question), and an edit is suggesting to include more than a single one of them?