Dharma

If you learn one Sanskrit word properly in this course, make it this one. Dharma is the hinge of Hindu ethical thought, and almost every English rendering of it is wrong in a different direction.

The lexicon's first sense is that which is established or firm, steadfast decree, statute, ordinance, law. Then: usage, practice, customary observance, prescribed conduct, duty. Then: right, justice. Then: virtue, morality, religion, religious merit, good works. The word is built on a root meaning to hold, to support, to bear up.

So the underlying picture is structural rather than devotional. Dharma is what keeps a thing being what it is, and what keeps the whole from collapsing. Everything that follows — duty, virtue, law, righteousness — is a specialisation of that.