What is growth retardation? Mom said I had it.

Slow growth. Some people grow more slowly (height and weight) than others, either naturally or because of outside influences such as medication or malnutrition or even abuse. "growth retardation" simply means that, compared to others your age and gender, you were growing more slowly than expected; this can be especially concerning it you start growing more slowly than you did, as can happen with stimuilants.