(anatomy) A triangular region that is a landmark in the neck, has its apex at the sternum pointing downward, and is bounded in front by the anterior midline of the neck, behind by the anterior margin of the sternocleidomastoid muscle, and above by the inferior margin of the lower jaw.

(anatomy) A triangular region that is a landmark in the neck, has its apex above at the occipital bone, and is bounded in front by the sternocleidomastoid muscle, behind by the anterior margin of the trapezius, and inferiorly by the middle third of the clavicle.

A region on the southern end of the Nouabalé-Ndoki National Park in the Republic of the Congo.

Alternative letter-case form of iron triangle

A region bounded by the vertices at Reno, Nevada, USA; Las Vegas, Nevada, USA; Fresno, California, USA; containing part of the Sierra Nevadas (a mountain range in the Rocky Mountain Cordillera); the triangle falling mostly in the U.S. state of Nevada; where many plane crashes occur and planes disappear.

(anatomy) Small zones lying between the costal and sternal attachments of the thoracic diaphragm.

(anatomy) An anatomical space in the superior and medial aspect of the anterior thigh, bounded superiorly by the inguinal ligament, laterally by the sartorius muscle, and medially by the adductor longus muscle.

A region of the Pacific Ocean, settled by Polynesians, that is roughly triangular, extending from vertexes approximately at New Zealand, Easter Island, Hawaii. This is sometimes used to define the region of Polynesia.

(anatomy) An area located in the superficial paraseptal endocardium of the right atrium.

(anatomy) A space in each lateral half of the neck that is bounded in back by the sternocleidomastoid muscle, below by the omohyoid muscle, and above by the stylohyoid and digastric muscles.