tʃˈɪldɹən wɪð fˈeɪlɪɹ tə θɹˈaɪv jˈuːʒuːəli hæv ɐ wˈeɪt ðæt ɪz bᵻlˌoʊ ðə θˈɜːd ɔːɹ fˈɪfθ pɚsˈɛntaɪl fɔːɹ ðɛɹ ˈeɪdʒ ænd ɐ dᵻklˈaɪnɪŋ ɡɹˈoʊθ vəlˈɑːsᵻɾi mˈiːnɪŋ ðeɪ ɑːɹ nˌɑːt ɡˈeɪnɪŋ wˈeɪt æz ɛkspˈɛktᵻd.
Children with failure to thrive usually have a weight that is below the 3rd or 5th percentile for their age and a declining growth velocity (meaning they are not gaining weight as expected).