As per Wikipedia,
In the theory of high-dimensional convex polytopes, a facet or side of a $d$-dimensional polytope is one of its $(d − 1)$-dimensional features, a ridge is a $(d − 2)$-dimensional feature, and a peak is a $(d − 3)$-dimensional feature.
I want to know is there any general name for an $(n-k)$ dimensional feature of an $n$-dimensional convex polytope?
The best you can hope for is something recursive like a $k$ face or something, because $n$ is arbitrary and we can't write down arbitrarily many names!
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