Noun

1. Any young mammal that has been recently weaned.
2. Specifically, a human child that has been recently weaned.

   In developing countries, weanlings are most at risk of malnutrition.

3. Specifically, a young horse that has been weaned from its mother, but is less than one year old (usually 5-12 months old).

   The weanling was sold to the local horse dealer