Of, pertaining to, or consisting of several ethnic groups.
In general, they are propagating the image of Ukrainians as the European descendants of good peasant stock, of multiethnic pioneers, and of an ancient multiethnic state.1993, Alexander J. Motyl, Dilemmas of Independence: Ukraine After Totalitarianism:
As a multicultural and multiethnic society, Singapore has four official languages: Malay, Mandarin, Tamil, and English, with Malay considered the national language and English as a nominally neutral ‘working language’ allowing communication across all communities.2019, Li Huang, James Lambert, “Another Arrow for the Quiver: A New Methodology for Multilingual Researchers”, in Journal of Multilingual and Multicultural Development, →DOI, page 3: