Synonyms of preposition

Noun

1. preposition, function word, closed-class word

usage: a function word that combines with a noun or pronoun or noun phrase to form a prepositional phrase that can have an adverbial or adjectival relation to some other word

2. preposition, place, position

usage: (linguistics) the placing of one linguistic element before another (as placing a modifier before the word it modifies in a sentence or placing an affix before the base to which it is attached)

Definition and meaning of preposition (Dictionary)