This is the 10171st most frequent German word.
pferd
Horse.
Here, 'Pferd' is used as the subject of the sentence, a noun referring to the animal.
Das Pferd galoppiert über die Wiese.
The horse gallops across the meadow.
'Pferd' functions as the object of the prepositional phrase 'auf einem Pferd', denoting the entity ridden, the horse.
Ich reite gern auf einem Pferd.
I like riding on a horse.
'Pferde' is the plural form of 'Pferd', indicating more than one horse as the direct object in the context of the sentence.