On this site we have many questions about triangular numbers, pentagonal numbers, pyramidal numbers and probably also some other related topics. (We might also consider square numbers, although at least some of the questions about them will fall under sums-of-squares and we also have a separate tag square-numbers.)
Would it be useful to have a separate tag for figurate numbers?
My personal opinion is that such tag might be useful, as there are many problems related to such numbers in number theory, in recreational mathematics and maybe also in some other areas.
EDIT: I have noticed only today that there is square-numbers (hence my addition above). I think that this tag should stay separate from figurate-numbers, since squares have somewhat special character.