English
inbetwixt
From in + betwixt.
Proto-Indo-European *h₁én ‘in’
Proto-Germanic *in
Proto-West Germanic *in
Old English in
Middle English in ‘inside’
English in
Proto-Indo-European *dwóh₁ ‘two’
…
Proto-Germanic *twiskaz ‘twofold, double’
Old English tweox ‘twofold’
Old English betweox ‘between’
Middle English bitwixe ‘in the meantime between two events’
English betwixt
Today it means
prep Between; in between.
Language periods are conventional ranges, not dates for this word.
Etymograph / inbetwixt