endocrinologist

n. expert in endocrinology, expert on the study of the endocrine glands and their secretions

Endocrinology is a branch of medicine dealing with disorders of the endocrine system and its specific secretions called hormones.
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Noun
1. physician who specializes in the diagnosis and treatment of conditions affecting the endocrine system
(hypernym) specialist, medical specialist
(hyponym) Turner, Henry Hubert Turner

[en-do-krih-NAH-lo-jist]
A doctor who specializes in diagnosing and treating hormone disorders.

a doctor who treats people who have endocrine gland problems such as diabetes.