What is the meaning of Epistemology?

The branch of philosophy dealing with the study of knowledge; the theory of knowledge, asking such questions as "What is knowledge?", "How is knowledge acquired?", "What do people know?", "How do we know what we know?", "How do we know it is true?", and so on.

A particular instance, version, or school thereof; a particular theory of knowledge.

Source: wiktionary.org