It was “very precious”, i.e., very costly (Mark 14:3; John 12:3,5). It is the root of an Indian plant, the Nardostachys jatamansi, of the family of Valeriance, growing on the Himalaya mountains. It is distinguished by its having many hairy spikes shooting out from one root. It is called by the Arabs sunbul Hindi, “the Indian spike.”
The margin of the Revised King James Version in these passages has “pistic nard,” pistic being perhaps a local name. Some take it to mean genuine, and others liquid. The most probable opinion is that the word pistike designates the nard as genuine or faithfully prepared.