Cow dreams symbolize diligence, wealth, and abundance. A fat, healthy cow appearing means increasing wealth and a more prosperous life. A cow entering your home is a lucky dream predicting great wealth incoming. Losing a cow warns of financial loss or losing something important.
Animals appearing in dreams — as in "Cow Dream" — often symbolize instinct or a suppressed impulse in Jung's theory of Archetypes. The specific animal and the emotion it evokes in you both shape the meaning far more than a generic dream dictionary entry can.
What was the first emotion you felt when you saw that animal in the dream?