At least when the ambient vector space is more than 3-dimensional, yeah. Specifically, a hyperplane generally refers to something with codimension 1. (So, when

At least when the ambient vector space is more than 3-dimensional, yeah. Specifically, a hyperplane generally refers to something with codimension 1. (So, when the ambient vector space is finite-dimensional, the dimension of a hyperplane is one less than the dimension of the ambient vector space.)