(grammar) An element that combines syntactically with a phrase and indicates how that phrase should be interpreted in the surrounding context; a preposition or postposition.
2008, Amani Bohoussou, Stavros Skopeteas, Grammaticalization of spatial adpositions in Nànáfwê, Elisabeth Verhoeven, Stavros Skopeteas, Yong-Min Shin, Yoko Nishina, Johannes Helmbrecht (editors), Studies on Grammaticalization, Walter de Gruyter (Mouton), page 77,
It is well known in West African linguistics that languages in this broad sense display adpositions that emerge out of these two sources, namely nouns and verbs.
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