late Old English cancer "spreading ulcer, cancerous tumor," from Latin cancer "malignant tumor," literally "crab" (see cancer); influenced in Middle English by Old North French cancre "canker, sore, abscess" (Old French chancre, Modern French chancre). The word was the common one for "cancer" until c.1700. Also used since 15c. of caterpillars and insect larvae that eat plant buds and leaves. As a verb from late 14c. Related: Cankered; cankerous. Canker blossom is recorded from 1580s.
canker can·ker (kāng'kər)
n.
Ulceration of the mouth and lips.
An acute inflammation or infection of the ear and auditory canal, especially in dogs and cats.
Cancrum.
a gangrene or mortification which gradually spreads over the whole body (2 Tim. 2:17). In James 5:3 "cankered" means "rusted" (R.V.) or tarnished.
disease of plants that is caused by numerous species of fungi and bacteria. Symptoms include round-to-irregular, sunken, swollen, flattened, or cracked, discoloured, and dead areas on the stem (cane), twig, limb, or trunk. Cankers may enlarge and girdle a twig or branch, killing the foliage beyond it. They are most common on plants weakened by mechanical, winter, or insect injury; drought; nutritional imbalances; nematodes; and root rot.