Failure to thrive (
FTT), more recently known as
faltering weight or
weight faltering, is a term used in
pediatric, adult as well as
veterinary medicine (where it is also referred to as
ill thrift), to indicate insufficient weight gain or inappropriate weight loss. When not more precisely defined, the term refers to
pediatric patients. In children, it is usually defined in terms of
weight, and can be evaluated either by a low weight for the child's age, or by a low rate of increase in the weight.