an meaning and definition in german
Preposition
Frequency: 
with an accusative or dative case object
The preposition an is used with an object in the accusative case if it indicates movement from one place to another, whereas it is used with the dative case if it indicates a location.It is usually used to refer to something being on a vertical surface, as opposed to auf, which usually points to a horizontal surface.
When followed by the masculine/neuter definite article in the dative case (i.e. dem (“the”)), the two words contract to am (“on the”).
When followed by the neuter definite article in the accusative case (i.e. das (“the”)), the two words contract to ans (“on the”).
- with a location in the dative case on; upon; at; in; against Das Bild hängt an der Wand. ― The picture hangs on the wall.
- with a time in the dative case on; in
- (with a dative case object) by; near; close to; next to
- (with a dative case object) by means of; by
- (with an accusative case object) on; onto Ich hänge das Bild an die Wand. ― I hang the picture on the wall.
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