Wean/wiːn/ Definition 1 of 2Pro Tip 1/3Gradual Process Weaning is often a slow transition rather than an instant change. Sarah's baby was gradually weaned onto solids over several weeks. Pro Tip 2/3Age Context The context of weaning usually involves infants or young animals. Puppies are usually weaned from their mother's milk at around eight weeks old. Pro Tip 3/3Physical Development Weaning indicates a step in growth or independence. Once kittens are weaned, they start exploring more on their own.