noun
Refers to one's spouse's father. The most common meaning.
義父は来月定年退職します。
My father-in-law will retire next month.
noun
A man who raises a child as his own without being the biological father. Less common than father-in-law.
彼は幼い頃から義父に育てられた。
He was raised by his foster father from a young age.
noun
A man who is married to one's biological mother but is not one's biological father.
義父とは最初はぎこちなかったが、今は仲が良い。
At first things were awkward with my stepfather, but now we get along well.