canker

A canker is a kind of sore. Some people are prone to getting cankers on their mouths. Canker can also refer to anything that is terrible and difficult to get rid of. Your parents might complain that the abandoned, run-down house two blocks away is a canker on your neighborhood.

In medicine, cankers are ulcers that are difficult to treat (the word is closely related to cancer). In agriculture, canker refers to a fungal disease that attacks the bark of trees. If one kid in your class misbehaves, and everyone suddenly follows his lead, that kid could be described (by your teachers) as a canker.

Primary Meanings of canker

1.
nv
an ulceration (especially of the lips or lining of the mouth)
become infected with a canker
2.
n
a pernicious and malign influence that is hard to get rid of
Full Definitions of canker
1

n an ulceration (especially of the lips or lining of the mouth)

Synonyms:
canker sore
Type of:
ulcer, ulceration
a circumscribed inflammatory and often suppurating lesion on the skin or an internal mucous surface resulting in necrosis of tissue

n a fungal disease of woody plants that causes localized damage to the bark

Type of:
plant disease
a disease that affects plants

v become infected with a canker

Type of:
come down, sicken
get sick

v infect with a canker

Type of:
infect
communicate a disease to
2

n a pernicious and malign influence that is hard to get rid of

“according to him, I was the canker in their midst”
Synonyms:
pestilence
Type of:
influence
a cognitive factor that tends to have an effect on what you do

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