同父 is read as どうふ (doufu) and means same father.
どうふ
doufu
どうふぼ
the same parents
おなじ
anyway
どうじ
simultaneous
どういつ
fair
どうい
same meaning
どうじん
same person
どうめい
homonym
どう
likewise
どうじょう
same as above
どうじつ
the same day
どうこく
the (said) country
どうげつ
the same month