The term "singular" in "singular simplex" refers to its deviation from the typical characteristics of a simplex, as singular homology focuses on continuous images of simplices that may not resemble them. This contrasts with simplicial homology, which deals with actual simplices. The definitions of "singular" as remarkable or odd align with the nature of singular simplices, which can include degenerate forms like points. There is no direct relationship between singular matrices and singular simplices, except in a very abstract sense involving degenerate simplices and their Jacobians. The discussion highlights the nuanced meaning of "singular" in mathematical contexts.