1.
If you describe a man as ~, you mean that he is like a boy in his appearance or behaviour, and you find this characteristic quite attractive.
She was relieved to see his face light up with a ~ grin...
He loves to learn, and has a ~ enthusiasm for life.
ADJ: usu ADJ n approval
~ly
John grinned ~ly.
ADV
2.
If you describe a girl or woman as ~, you mean that she looks like a boy, for example because she has short hair or small breasts.
...her tall, ~ figure.
ADJ