That depends. If you've been in a relationship with him, it likely means that he, well, loves you.
On the other hand, if you've just been on a date or two or none at all, he's likely trying to attach himself to you and cement a relationship. He probably believes what he says, but that may change as it's not based upon anything concrete. Basically it's a plea for romantic attention.
Putting it crudely, he could just be trying to get your knickers off.
Does he do air quotes with his hands when he says it?
yeah , probs, if he says it in a none joking way
she'll cry!
if you feel the same way about him then say i love you back.
Tell him to make up his mind! you can only have one true love!
If he smiles at you, bumps into you, if he says he likes or "loves" you stuff like that
that means he loves or hates you still he might love you!
He means that he loves you and wouldn't let anything happen to you.
Probably because he is insecure, this is a sign of immaturity and direspect.
No, he meant that he loves you as a friend not as a mate.
One way you could tell is if he says it in front of his friends, and isn't afraid to show it in front of other people.
As I understand it, it would indicate that he wants sex with you. It does however not imply that he loves you.