ORIGINAL: timbercruiser
When you clarified and said 7 month old deer then it sounds better, that is a yearling.. I call any deer over about 4 months old as a yearling. Fawns are (to me) spotted or recently spotted little deer.
A yearling is an animal between one year of age and two years of age. A 7 month old deer is a fawn. You can call a 4 month old fawn a yearling if you want to, but I don't know a deer manager in this country who calls a 4 month old deer anything other than what it is, a fawn.