noun
biological father; real father; natural father
Refers to one's biological father, as opposed to an adoptive, step, or foster father. Often used in formal or legal contexts, or when clarifying family relationships.
See also: 実母
彼は実父の顔を知らない。
He doesn't know his biological father's face.
戸籍には実父の名前が記載されている。
The biological father's name is recorded in the family register.