What does it mean when a dog leans into you?

Leaning can mean many different things. Just like tail wagging, it is not always a good thing. Sometimes it's her asking for attention, sometimes it's establishing dominance, and sometimes it's being protective. My guess is she is establishing dominance or protecting you. She could be showing her dominance over the cat, to keep her away from you which would be in a sense protection. Or she could find the cat a threat and is protecting you. Either way, it's harmless behavior as long as it doesn't bug you.

Dogs like to know that someone is there for them. I have a medium dog that does that. She doesn't like being alone and will lean against me when standing to know if I'm still by her side.

Dog loves you does not trust the cat

She is probably just being protective or wants attention. she might want attention so much that she becomes over protective. or it could be nothing at all and she just does that. there are a lot of possible answers to that.

She loves you. And she is trying to protect you from those awful cats.

It's a dog hug. I read it in this one book and heard it on this dog show on T.V.

Hah. lucky you!! your gaint dog loves giving you hugs!!

he loves you. its like a dog petting you.

It's about to pee on you