“what you are made to do” or “what you should be doing.”* Sanskrit from swa (own) + dharma (duty) .
The ancient text, The Bhagavad-Gita says Swadharma is action harmonized with our inborn nature: talents, values, callings. It leads to fulfillment in life.( Gita, 3 . 27–35 ).
The Lord Krishna says (in Gita, chapter 3, verse 35):
śhreyān swa-dharmo viguṇaḥ para-dharmāt sv-anuṣhṭhitāt
swa-dharme nidhanaṁ śhreyaḥ para-dharmo bhayāvahaḥ
Translation: “It is far better to perform one’s natural prescribed duty, even with faults, than to perform another’s prescribed duty, even if perfectly. In fact, it is preferable to die in the discharge of one’s duty, than to follow the path of another, which is fraught with fear.”
Contrast with dharma, which is a generallized sense of duty, applicable to everyone (sometimes all of a particular situation or station)
*as translated by Stephen Mitchell