Pronoun
oneself (itself, etc.)
Poetical term
他人を己を持って計ってはいけない。You must not judge others by yourself. I; me
Humble (kenjougo) language
you
Derogatory
Adverb (fukushi)
by oneself (itself, etc.)
Interjection (kandoushi)
interjection expressing anger or chagrin
Also written 己れ【おのれ】