Examples: cartography card archaeology archetype monarchy legal loyal purse personal cinema kinase car carpenter hippopotamus Mesopotamia dative data date
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Proto-Indo-European *oḱtṓw

→ English October (derived)
→ English eight (inherited)
→ English octagon (derived)
→ Avestan 𐬀𐬱𐬙𐬀 (inherited)
→ Avestan 𐬀𐬱𐬙𐬆𐬨𐬀 (derived)
→ Afrikaans agt (inherited)
→ Aragonese ueit (inherited)
→ Aragonese ueito (inherited)
→ Aragonese güeito (inherited)
→ Old English eahta (inherited)
→ Assamese আঠ (derived)
→ Baluchi ہشت (inherited)
→ Belarusian восем (derived)
→ Bulgarian осем (inherited)
→ Bengali আট (inherited)
→ Bengali আষ্ট (inherited)
→ Breton eizh (inherited)
→ Catalan vuit (inherited)
→ Central Kurdish ھەشت (inherited)
→ Corsican ottu (inherited)
→ Czech osm (derived)
→ Kashubian òsmë (derived)
→ Old Church Slavonic осмь (derived)
→ Welsh wyth (inherited)
→ Danish otte (inherited)
→ German acht (inherited)
→ Lower Sorbian wósym (inherited)
→ Middle Dutch achte (inherited)
→ Emilian ôt (inherited)
→ Greek οκτώ (inherited)
→ Middle English eighte (inherited)
→ Spanish ocho (inherited)
→ Persian هشت (inherited)
→ Fijian Okotova (derived)
→ Faroese átta (derived)
→ French huit (inherited)
→ West Frisian acht (inherited)
→ Irish ocht (inherited)
→ Scottish Gaelic ochd (inherited)
→ Crimean Gothic athe (inherited)
→ Old Swedish atta (derived)
→ Old High German ahto (inherited)
→ Gothic 𐌰𐌷𐍄𐌰𐌿 (derived)