User:Quercus solaris/When blindness of a passage is not atresia

Linguistic science explains why a blind fistula is almost never called an atretic fistula in real-world biomedical usage.

An atretic structure is a blind one, but more specifically, it is, connotatively, one whose blindness is undesirable, because atresia is, connotatively, undesirable blindness of a normally patent structure—even if denotatively it can be any blindness of any structure.