Dharma in both Hinduism and Buddhism refers to the principle or law that orders the universe. In Buddhism, the word in particular points to the law of karma and rebirth.
Because this law was recognized and formulated by the historical Buddha, dharma is most commonly used in Buddhism to mean "the teachings of the Buddha."
In Theravada Buddhism, dharma is a term for the factors of existence, or the transitory conditions that cause phenomena to come into being.
Dharma is also sometimes used to refer to ethical rules and to mental objects or thoughts.