imaginary horse
nounUK /ɪˈmædʒɪnəri hɔːs/
US /ɪˈmædʒəneri hɔːrs/
A horse you make up in your mind that is not really there.
My little sister rides her imaginary horse around the garden every afternoon.
OTHER MEANINGS
2. A toy horse a child pictures and plays with as if it were alive.
He galloped across the room on his imaginary horse, neighing loudly.
3. A hoped-for horse that does not exist, such as one wished for but never owned.
Her imaginary horse was always a white stallion with a golden mane.
4. Something people talk about as if real but which has no actual existence.
The promised pony ride turned out to be an imaginary horse.