noun: cashmere; plural noun: cashmeres
fine soft wool, originally that from the Kashmir goat.
woolen material made from or resembling cashmere.
“a cashmere sweater”

Late 17th century: an early spelling of Kashmir.

Pashima Cashmere Goats
Pashima Cashmere Goats

In the United States, under the U.S. Wool Products Labeling Act of 1939, as amended, (15 U. S. Code Section 68b(a)(6)), states that a wool or textile product may be labeled as containing cashmere only if:

such wool product is the fine (de-haired) undercoat fibers produced by a cashmere goat (Capra hircus laniger);
the average diameter of the fiber of such wool product does not exceed 19 microns; and
such wool product does not contain more than 3 percent (by weight) of cashmere fibers with average diameters that exceed 30 microns.
The average fiber diameter may be subject to a coefficient of variation around the mean that shall not exceed 24 percent.[4]

Cashmere is probably the finest wool available.  It’s both very warm and very soft.  No wonder it’s known as “thread of the kings”.  It’s the undercoat from Capra hircus laniger, the cashmere goat. The best Cashmere traditionally comes from Central Asia: notably Mongolia and China, Australia and New Zealand, where the conditions seem to encourage the best wool quality.  Other countries raise cashmere, but only a few match the Asian quality.

Once the downy fur is woven into yarn, it can be knitted or woven into garments.  Buy your cashmere from reputable sources because there are a lot of fakes out there.  It should be very soft and very light.  And it shouldn’t scratch at all when rubbed against a cheek.