Definition of "morbus"

I thought he were took with the Morbus one day, I did with his nasty angle!For “oh dear,” says he, and burst out in a cry, “oh my gut is all got of a tangle!”

1838, Thomas Hood, “A Rise at the Father of Angling”, in The Comic Annual, page 47

Probably no small share of our cholera morbuses, diarrhœas, and dysenteries, have their origin in this source.

1846, William Andrus Alcott, The Young House-keeper: Or, Thoughts on Food and Cookery, page 214

Unfortunately, most of the morbi accepted in modern medicine are only taxonomic entities whose causal derivation is merely partially known and therefore polygenic.

1979, F. Kraupl Taylor, D. M. K. Taylor, The Concepts of Illness, Disease and Morbus, page 117