We were just having a discussion on the use of meta tags on synonym-request posts. Some use discussion, while others use feature-request. We should have a standard for this, instead of picking tags willy-nilly.
\$\begingroup\$ I think this can also be applied to the burninate-request tag. \$\endgroup\$– Simon ForsbergJul 4, 2015 at 18:43
I'd go with discussion. Not exactly because it's perfectly suited for the job... but because the other three required tags are more clearly incorrect. And it does sort of fit; it'll probably take some community discussion to hash out whether a given synonym is correct or not before anyone takes any action.
The excerpt of the feature-request tag says:
You have an idea for a new feature, or for a change to the existing functionality.
I don't think a synonym-request is either of those.