Estonian üks

← Finnish yksi (cognate)

← Proto-Finnic *ükci (inherited)

→ Estonian üksteist (compound)

→ Estonian ükssarvik (affix)

→ Estonian ühine (mention)

→ Estonian ühendama (affix)

→ Estonian üksik (suffix)

→ Estonian üksi (mention)

→ Estonian igaüks (compound)

→ Finnish yksi (cognate)

→ Ingrian yks (cognate)

→ Komi-Permyak ӧті (cognate)

→ Karelian yksi (cognate)

→ Livonian ikš (cognate)

→ Moksha фкя (cognate)

→ Erzya вейке (cognate)