I know there has to be one.
A quick archive search turned up this GQ thread on the same question.
Short answer: nasal secretions, nasal concretions, or mucus plugs, or rhinoliths - there is no one, standard, term.
Back a number of years ago my ex-wife had some sinus surgery done at Johns Hopkins by a top specialist in that field. It was pretty gross, and it involved multiple return visits over the next couple months so that he could stick a small long-handled spoon up her nose and scrape away at the bone inside her sinuses, without anesthetic. (My ex said, “You get used to it.”)
Anyway, I asked her what medical term the doctor used for boogers, and she said that he and the other doctors used “crusts” or “crusting.” (I didn’t think to ask her about snot, which would be the semi-liquid version of the same thing.)
I’m not saying that’s the official term. But it’s the one they used day-to-day at that hospital.
mucus (mu’kus) - the free slime of the mucous membranes, composed of secretion of the glands, various salts, desquamated cells, and leukocytes. (Dorland’s Medical Dictionary).