Definition;Preposition

Preposition (Noun)

 * 1) A word governing, and usually preceding, a noun or pronoun and expressing a relation to another word or element in the clause, as in “the man on the platform,” “she arrived after dinner,” “what did you do it for?”
 * 2) Any member of a class of words found in many languages that are used before nouns, pronouns, or other substantives to form phrases functioning as modifiers of verbs, nouns, or adjectives, and that typically express a spatial, temporal, or other relationship, as in, on, by, to, since.                                                          
 * 3) A word (one of the parts of speech) that shows the relationship between a noun or pronoun and other words in a sentence. Prepositions commonly convey the following relationships: comparison(like, as); direction(to, towards, through); place(at;by;on); possession(of); purpose(for); source(from, out of); and time(at, before, on)