noun

• (uncountable) An academic discipline that seeks truth through reasoning rather than empiricism, often attempting to provide explanations relating to general concepts such as existence and rationality.
  "Philosophy is often divided into five major branches: logic, metaphysics, epistemology, ethics and aesthetics."
• (countable) A view or outlook regarding fundamental principles underlying some domain.
  "a philosophy of government; a philosophy of education"
• (countable) A general principle (usually moral).
  "As a matter of fact the Enlightment culture was based on a philosophy inspired to an ethical laicism whose aim was to create a better society based on principles such as solidarity, equality of rights and duties, and full freedom."
• (countable) A comprehensive system of belief.

verb

• (now rare) To philosophize.
  "Plato hath (in my seeming) loved this manner of Philosophying, Dialogue wise in good earnest, that therby he might more decently place in sundry mouthes the diversity and variation of his owne conceits."