Definition of "benign"

benign

/bɪˈnaɪn/

adjective
comparative benigner or more benign, superlative benignest or most benign
1. Kind; gentle; mild.
  Quotations
  But though we both entertained these ideas, we differed in their application. Resentment added also a sting to my censure; and I reprobated Raymond's conduct in severe terms. Adrian was more benign, more considerate.
  1826, [Mary Shelley], chapter IX, in The Last Man. […], volume I, London: Henry Colburn, […]
2. (of a climate or environment) mild and favorable
3. (in combination) Not harmful to the environment.
4. (medicine) Not posing any serious threat to health; not particularly aggressive or recurrent.