gradually deprive (infants and young mammals) of mother's milk
She weaned her baby when he was 3 months old and started him on powdered milk. The kitten was weaned and fed by its owner with a bottle.
source: WordNet 3.0
detach the affections of
source: WordNet 3.0
To accustom and reconcile, as a child or other young animal, to a want or deprivation of mother's milk; to take from the breast or udder; to cause to cease to depend on the mother nourishment.