An informal, affectionate term for "father" (daddy, dad), used mainly by children or in familiar speech.
父ちゃん、明日の運動会は来られる？
Dad, can you come to tomorrow's sports day?
子供がまだ『父ちゃん』と呼んでいる。
The child still calls him 'Dad' (father).
あの町ではお年寄りでも息子を『父ちゃん』と呼ぶことがある。
In that town, even older people sometimes call their sons '父ちゃん' (colloquial).
彼は家族から『父ちゃん』と親しげに呼ばれている。
He is affectionately called 'Dad' by his family.