What does 'sort of ' mean?
I actually often hear this word but don't know the meaning.

Question

Answer

'Sort of' isn't a word! It's more of a phrase, like 'Kind of'. Here's some examples:

It's a sort of an ugly dog.
and
I kind of feel bad about it.

'Sort of' and 'Kind of' are informal fillers to denote something vague.

Answer

It means "a little bit"

"He is sort of lazy" = "He is a little bit lazy."
"I'm sorta hungry" = "I'm a little bit hungry."