Meaning of ITSELF in English

ITSELF

pron. emphatic and refl. form of IT(1).

Phrases and idioms:

by itself apart from its surroundings, automatically, spontaneously. in itself viewed in its essential qualities (not in itself a bad thing).

Etymology: OE f. IT(1) + SELF, but often treated as ITS + SELF (cf. its own self)

Oxford English vocab.      Оксфордский английский словарь.