the.com/yeast infection

means An overgrowth of naturally occurring Candida fungus (usually Candida albicans) causing itching, discharge, and irritation, typically when the normal balance of vaginal microflora gets disrupted by antibiotics, hormones, or other changes.

from "Yeast" traces back to Old English "gist," related to Germanic and Greek words connected to boiling or foaming — fitting for a fungus that ferments and bubbles when it overgrows. "Infection" comes from Latin "inficere," meaning to dip, taint, or stain. The word itself is old; the clinical phrase is a plain, unglamorous mashup — medicine naming the problem exactly as it is, no poetry involved, which is probably why actual sufferers had to supply the poetry themselves.