Catch-up growth : a term used to describe a rate of growth that is faster than expected. For infants born with low birthweights or small for gestational age, catch-up growth can describe gains in weight or length where the measurement reaches the 5th percentile for age (when it had previously been below the 5th percentile). In other instances, catch-up growth refers to weight and/or height gains when a child who has experienced stunted growth receives adequate energy and protein.