Blavatsky
Original sense
Dharma is the law of a being’s true nature and the duty that follows from it — not a lifestyle brand. For a Theosophist, she said, dharma includes the unpaid work of brotherhood and the study of truth. It is paired with karma: karma is what you have done; dharma is what, given that, you ought to do.
Dharma is the one law of conduct that is in agreement with the nature of the cosmos and of man.
She used the word less systematically than karma. Later Theosophy and then New Age filled it with ‘life purpose’ language she would have found too personal and too comfortable.