from The Century Dictionary and Cyclopedia
- n. Aphthous ulcer of the mucous membrane in the angle between the lip and the gum.
Sorry, no etymologies found.
In the good old days when decoctions of any herb that was particularly nauseous were swallowed in the simple faith that virtue resided in them in proportion to their revolting taste, the gold-thread's bitter roots furnished a tea much valued as a spring tonic and as a cure for ulcerated throats and canker-sore mouths of helpless children.
Well, that's where I Think I caught it, the first time I ever had a canker-sore, right on the end of my nose.
That's when his passion for inventing collided with his training as a chemist to solve his aggravating canker-sore problem.