10 is an important figure (=ALL 10 fingers on 2 hands): KÜMME (Est.), KYMMENEN (Fin.), KHUMI (Chewa); KUMI (Swahili), GUMI (chiShona); GOMA (Hausa); HAMAR (Basque), KAUM (H'Mông); 'UMA (Hawaiian), ON (Turkish), U (Sumerian).
Similarly important is 5 (=ALL 5 fingers on 1 hand): [KHMS] (Arabic). And [AL-ZUMA’A] (Arabic), CUMA (Turk.), CÜMƏ (Azeri), JUMA (Uzbek), ЖҰМА [ŽÜMA] (Kazakh) - is Friday, 5th day of the week.
The semantics is 'gathering all (5 or 10 fingers) together': CEM (Turk.), CƏM (Azeri), JAMI (Uzbek), [LA-JUMEA] (Arabic) - ‘a SUM, a JAM, a total, a gathering, an aggregate’; CUM (Latin), CON (Ital.), CHOMH, CUMA (Irish) - ‘together with’; KUMMAGI, KUMBAGI (Est.) - ‘both’; KUMANA, KOMANA (Chewa) - ‘gather’; KUMIKA (Chewa) - ‘find, gather’; KOMBE (Chewa) - fishing net; etc.
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Similarly, 5 is VIIS (Est.), VIISI (Fin.). Compare to ВСЕ [VSE] (Rus.) - ALL, everybody.
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Ever thought of the correspondence of the Roman numbers - and the Finno-Ugric marking of 8 and 9 ?
IIX (old variant of VIII) - kah(d)eksa, kah-deksan (10 less 2).
IX - üh(d)eksa, yh-deksän (10 less 1).