nidan verb (lower class) with 'ru' ending (archaic), intransitive verb
be violated; be corrupted; be polluted; be stained
Archaic intransitive verb meaning to become impure, defiled, or morally stained. The modern equivalent is 穢れる (けがれる).
See also: 穢れる
古典では「心が汚る」のように使われた。
In classical texts, it was used like 'the heart becomes defiled'.
Modern intransitive verb with the same meaning; 汚る is its archaic predecessor.
Archaic verb; the exact derivation is uncertain, but it is related to the modern 穢れる (けがれる).