retardation
noun [ U ] formal uk/ˌriː.tɑːˈdeɪ.ʃən/ us/ˌriː.tɑːrˈdeɪ.ʃən/
迟缓;阻滞;延迟
slow development, or development that is slower than it should be
Severe iron deficiency can cause developmental delay and growth retardation. 严重缺铁会导致发育迟缓。