adposition, adpositional: Languages usually have short words (such as "in", "during", and "of") which express a static relationship with respect to a noun phrase or other nominal element (its object), for example a locative, temporal, or possessive relationship. If they precede the object they are called prepositions, and if they follow it they are called postpositions. English, Spanish, and many other languages of the world (including the Otomanguean and Mayan languages of Mexico) have prepositions; other languages (such as the Uto-Aztecan languages) use postpositions to express similar concepts. Together the two classes form the class of adpositions. Adpositions are transitive [4].

An adposition with its object can modify either a noun (in which case it is adjectival) or a verb (in which case it is adverbial), i.e. adpositions can be used to express relationships of either things or processes with respect to their objects. For example, in "the book on the floor", the book is located with respect to the floor, and this constitutes an adjectival use of the prepositional phrase "on the floor". In "it fell on the floor", however, it is the (end point of the) process of falling that is located with respect to the floor, so this is an adverbial use of the prepositional phrase.

Adpositions may be completely independent words, or they may be attached more or less tightly to their objects, to the point of being (in some sense) affixes; in this case they may be called adpositional clitics or affixal adpositions. This is especially common with postpositions. For example, the Orizaba Nawatl form "nopan" 'on me' has the postpositional suffix "-pan" 'on' attached to its object "no-" 'me'. Similarly, 'on the ground' comes out in Nawatl as "tlâlpan", with "-pan" attached to its object "tlâl" 'earth, ground'. [Spanish: adposición, adposicional]