To "fatally" screw up someone's "natural" or "normal"
progression into
maturity; two of the most common forms of this abuse are to either invalidly/excessively tell a tender/naive-minded
little one to "grow up already", or to put down an adult by "treating him like a five-year-old".
I signed up for adult-counselling in an effort to get my social screws tightened, and they did an excellent job --- one
big way they helped me was to
teach me to recognize when others were trying to youthanize me, and then simply disregard these verbal
barbs so that they could no longer hurt me emotionally.