English
father-to-be
From father + -to-be.
Proto-Indo-European *ph₂tḗr
Proto-Germanic *fadēr
Proto-West Germanic *fader
Old English fæder
Middle English fader ‘a father’
English father
Today it means
noun A male partner of a pregnant woman (mother-to-be), especially when she is pregnant for the first time.
Language periods are conventional ranges, not dates for this word.
Etymograph / father-to-be