noun
Refers specifically to one's own home or residence. Not used for 'one's own' in a general possessive sense.
彼は自家で小さな工房を開いている。
He runs a small workshop at his own house.
noun-modifying (irregular)
Prenominal modifier meaning 'one's own' or 'self-'. Common in compounds like 自家製 (homemade) and 自家用 (for personal use). 'Autologous' is a medical term (e.g., 自家移植).
このジャムは自家製です。
This jam is homemade.
自家用車で通勤している。
I commute by private car.