- a two-lobed endocrine gland, located at the base of the neck that secretes two hormones that regulate the rates of metabolism, growth, and development.
- an endocrine gland of vertebrates, consisting in man of two lobes near the base of the neck. It secretes hormones that control metabolism and body growth
- A two-lobed endocrine gland located in front of and on either side of the trachea and producing various hormones, such as calcitonin.
- A two-lobed gland that wraps around the trachea and is located at the base of the neck in vertebrate animals. The thyroid gland secretes two important hormones: thyroxine, which regulates the cell metabolism necessary for normal growth and development, and calcitonin, which stimulates the formation of bone and helps regulate the amount of calcium in the blood.