canker

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. Ulceration of the mouth and lips.
2. n. An inflammation or infection of the ear and auditory canal, especially in dogs and cats.
3. n. A condition in horses similar to but more advanced than thrush.
4. n. A localized diseased or necrotic area on a plant part, especially on a trunk, branch, or twig of a woody plant, usually caused by fungi or bacteria.
5. n. Any of several diseases of plants characterized by the presence of such lesions.
6. n. A source of spreading corruption or decay.
7. v. To attack or infect with canker.
8. v. To infect with corruption or decay.
9. v. To become infected with or as if with canker.

Century Dictionary and Cyclopedia

1. n. A cancerous, gangrenous, or ulcerous sore or disease, whether in animals or plants; hence, any corroding or other noxious agency producing ulceration, gangrene, rot, decay, etc.
2. n. Specifically— Cancrum oris (which see, under cancrum).
3. n. A disease or fungus attacking trees or other plants and causing slow decay.
4. n. In farriery, a disease in horses' feet, causing a discharge of fetid matter from the cleft in the middle of the frog, generally originating in a diseased thrush.
5. n. A canker-worm or insect-larva that injures plants by feeding on them.
6. n. Figuratively, anything that corrodes, corrupts, destroys, or irritates; irritation; pain; grief; care.
7. n. Rust.
8. n. In botany: The canker-rose or field-poppy, Papaver Rhæas.
9. n. The wild dogrose, Rosa canina.
10. n. A toadstool.
11. To infect with canker, either literally or figuratively; eat into, corrode, or corrupt; infect as with a poisonous influence; render ill-conditioned or venomous; make sour and ill-natured.
12. To corrode; grow corrupt; be infected with some poisonous or pernicious influence; be or become ill-conditioned or malignant.
13. To fret; become peevish.
14. To decay or waste away by means of any noxious cause; grow rusty or discolored by oxidation, as a metal.
15. n. An irregular excrescence on the trunks or branches of woody plants, caused by the perennial effort of the tissues to overcome an injury. Cankers may be originated by various causes, such as accidental wounds, injuries by frost, insects, fungi or bacteria, or various combinations of these.
16. n. A disease of fowls affecting the mouth and windpipe. It produces ulceration and often ends in death.

Wiktionary

1. n. botany A plant disease marked by gradual decay.
2. n. A corroding or sloughing ulcer; especially a spreading gangrenous ulcer or collection of ulcers in or about the mouth.
3. n. Anything which corrodes, corrupts, or destroys.
4. n. A kind of wild, worthless rose; the dog rose.
5. n. An obstinate and often incurable disease of a horse's foot, characterized by separation of the horny portion and the development of fungoid growths. Usually resulting from neglected thrush.
6. n. An avian disease affecting doves, poultry, parrots but also birds of prey caused by Trichomonas gallinae
7. v. transitive To affect as a canker; to eat away; to corrode; to consume.
8. v. transitive To infect or pollute; to corrupt.
9. v. intransitive To waste away, grow rusty, or be oxidized, as a mineral.
10. v. To be or become diseased, or as if diseased, with canker; to grow corrupt; to become venomous.

GNU Webster's 1913

1. n. A corroding or sloughing ulcer; esp. a spreading gangrenous ulcer or collection of ulcers in or about the mouth; -- called also water canker, canker of the mouth, and noma.
2. n. Anything which corrodes, corrupts, or destroy.
3. n. (Hort.) A disease incident to trees, causing the bark to rot and fall off.
4. n. (Far.) An obstinate and often incurable disease of a horse's foot, characterized by separation of the horny portion and the development of fungoid growths; -- usually resulting from neglected thrush.
5. n. A kind of wild, worthless rose; the dog-rose.
6. v. To affect as a canker; to eat away; to corrode; to consume.
7. v. To infect or pollute; to corrupt.
8. v. obsolete To waste away, grow rusty, or be oxidized, as a mineral.
9. v. To be or become diseased, or as if diseased, with canker; to grow corrupt; to become venomous.

WordNet 3.0

1. n. an ulceration (especially of the lips or lining of the mouth)
2. n. a pernicious and malign influence that is hard to get rid of
3. v. infect with a canker
4. v. become infected with a canker
5. n. a fungal disease of woody plants that causes localized damage to the bark