People

father

Source:*otьcьProto-Slaviccertain

The second yer gives e in Russian, Polish and Czech but a in BCS (otac) — the BCS yer reflex.

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English

father

Polish

ojciec

ˈɔjtɕɛts

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In all five languages

BCS script

Latin under Cyrillic

Russian
оте́цotec
ɐˈtʲetsinherited
Ukrainian
ба́тькоbatʹko
ˈbatʲkɔdifferent word · a Slavic nursery word bat- (cf. Russian ба́тя)
оте́ць exists, mostly in church and formal language.
Polish
ojciec
ˈɔjtɕɛtsinherited
Czech
otec
ˈotɛtsinherited
Bosnian-Croatian-Serbian
otacотац
ˈotatsinherited
English
father