This is nothing but removing part of the thyroid gland. Procedures like lobectomy (removal of a lobe of thyroid) and a hemithyroidectomy (removal of a part of thyroid) can be used to treat benign nodules. Only one section of the thyroid gland is removed. What this means is that, some thyroid tissue is left in place to continue functioning.
This involves removing most of the thyroid gland. This is useful to treat hyperthyroidism, multinodular goiter, or cancer.
A total thyroidectomy removes the entire thyroid gland. With these procedures, there is no thyroid tissue left behind.