Saw a show on tv and they mentioned something called hypoparathyroidism. What is that?

Low PTH, low calcium. The parathyroid glands are 4 little glands in the neck that make a hormone called PTH that regulates calcium metabolism. Hypoparathyroidism is when the parathyroid are under active, which results in low levels of calcium in the blood.
Definition. Hypoparathyroidism is low or absent parathyroid hormone resulting in symptoms of (and levels of) low calcium. See Pubmed ID # 26135962.