expression, noun
one's own property; possessions
Refers to something one owns or treats as one's own. Often used in set phrases like 我が物顔 (acting as if one owns the place) or 我が物にする (to make something one's own).
彼は会社を我が物顔で仕切っている。
He runs the company as if he owns it.
その土地を我が物にしようと企てた。
They schemed to make that land their own.
所有物 is a more formal, legal term for 'property' or 'belongings', while 我が物 is an everyday expression emphasizing personal ownership or possessiveness.
Compound of 我が (wa ga, 'my') and 物 (mono, 'thing'). The exact historical derivation is straightforward; the phrase has been used since classical Japanese to mean 'one's own thing'.