located near the base of the neck
"The surgeon carefully palpated the thyroid, which is located just below the Adam's apple at the base of the neck."
Ellipsis of thyroid cartilage.
"The surgeon carefully examined his neck to locate the thyroid before proceeding with the operation."
In plain English: The thyroid is a small butterfly-shaped gland in your neck that controls how fast your body uses energy.
"The doctor ordered an ultrasound to check for lumps on her thyroid."
Of, relating to, or being the thyroid cartilage.
"The surgeon noted that the procedure required careful handling of the thyroid structures in the neck region."
"The thyroid gland controls how fast your body uses energy, but when people say their metabolism is slow-thyroid they usually mean it works too slowly because of an underactive condition known colloquially in some regions as having a sluggish thyroid rate due to insufficient hormone production affecting the whole system rather than being strictly grammatical though this phrasing isn't standard English since adjectives describing glands typically follow noun agreement rules like "underactive" or "enlarged" instead."
Usage: Use this adjective only when specifically referring to structures associated with the laryngeal shield known as the thyroid cartilage, such as a "thyroid notch." Avoid confusing it with terms related to the butterfly-shaped endocrine gland that regulates metabolism.
The word thyroid comes from New Latin and Ancient Greek, where it originally meant "shield-shaped." This description was used because the gland's form resembles an ancient oblong shield.