Hypothyroid

Part of speech: adjective

Definitions

1. A medical condition marked by decreased hormone output from the thyroid gland, which can lead to symptoms like tiredness, weight gain, and cognitive changes
2. This state involves an insufficient hormonal production by the thyroid, impacting metabolism and resulting in symptoms such as lethargy and increased sensitivity to cold
3. A condition characterized by a deficiency in thyroid hormone production, leading to various metabolic issues and symptoms including fatigue, weight gain, and potential cognitive impairment

Etymology: The "thyroid" in "hypothyroid" is itself a Greek compound meaning "shield-shaped," and it was named for the gland's appearance rather than its function. Ancient Greek "thureos" meant a large oblong shield, and "-eidēs" means "resembling," so "thureoeidēs" described something shaped like that shield. New Latin scholars borrowed the Greek into "thyreoīdēs," and English adopted it as "thyroid," applied to the butterfly-shaped gland in the neck. "Hypo-" is the Greek prefix meaning "under" or "less than," so "hypothyroid" literally means "under-thyroid." It is simply a compound of that prefix and "thyroid," describing a condition in which the gland produces too little hormone.

Synonyms: underactive thyroid, hypothyroidism

Antonyms: hyperthyroid, overactive thyroid