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one's father; one's old man; dad; pops
middle-aged (or older) man; old man; geezer
one's boss
proprietor (of a restaurant, store, etc.); landlord
grizzly bear
親父の口癖を最近自分も使っていることに気づいた。
I realized I've been using my old man's catchphrases lately.
親父は頑固だが心の優しい人だった。
My old man was stubborn but kind-hearted.
飲み屋の親父が気さくに話しかけてきた。
The owner of the bar casually started talking to me.