Definition of superlative for English Language Learners. grammar : the form of an adjective or adverb that is used to indicate the greatest degree of a particular quality : the superlative form of an adjective or adverb.
The body's systems speed up and cause symptoms that are common to hyperthyroidism when thereâs a high level of thyroid hormone in the bloodstream. Symptoms include: 1  anxiety. 2  irritability. 3  fatigue. 4  hand tremors. 5  increased or irregular heartbeat.6  excessive sweating. 7  difficulty sleeping.8  diarrhea or frequent bowel movements.he body's systems speed up and cause symptoms that are common to hyperthyroidism when thereâs a high level of thyroid hormone in the bloodstream. Symptoms include: 1  anxiety. 2  irritability. 3  fatigue. 4  hand tremors. 5  increased or irregular heartbeat. 6  excessive sweating. 7  difficulty sleeping. 8  diarrhea or frequent bowel movements.
The most common cause of hypothyroidism is inflammation of the thyroid gland, which damages the glandâs cells. Autoimmune diseases. The most common cause of hypothyroidism in adults is autoimmune thyroiditis or Hashimotoâs disease. Atrophy of the thyroid gland. The thyroid gland shrinks in size as a result of aging.