They have the same meaning. The only difference is who you are talking to. The word 'grown-up' is mainly used when adults are talking to children, or when small children are talking among themselves. 'Grown-ups' is used in much the same way as French people say 'les grands' when they are talking to children about adults. We also have the adjective 'grown-up' to mean the opposite of 'childish'. For example, if a child acts in a mature way, you could say that they are 'being very grown-up'. Adults can sometimes use this childhood language in a slightly jokey way. For example, when a twenty-something buys his or her first business suit to wear for work, they might describe it as 'grown-up' clothes.

The only difference that I can tell is that 'grown-up' is used more for children. When you speak to children, you can adults 'grown-ups '. Children will often use grown-up because adults have literally 'grown up '. Apart from that there is no real difference but as an adult you should use 'adult' and not 'grown up' as it can sound childish. I hope this helps.

what is the difference between grown ups and adults

you are an grown up if you use italki but if you watch something uncensored on youtube then you become adult.Got it.This is the perfect answer to this question