As a result of this question:
Merge 'round' and 'rounded' tags
The rounded and round are being removed, and replaced with rounded-corners or number-rounding (note, this one existed before that question) where appropriate.
The rounding tag still exists, and has the following tag wiki:
Rounding a numerical value means replacing it by another value that is
approximately equal but has a shorter, simpler, or more explicit
(Note, I've changed the above, as the previous version didn't explain things clearly)
That said, I think that we should merge the rounding tag into the number-rounding tag (or preferably, a new tag, numerical-rounding as that name feels more proper).