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a three-cornered object, figure, or area, such as a delineated area on the surface of the body; called also trigone.
carotid triangle, inferior that between the median line of the neck in front, the sternocleidomastoid muscle, and the anterior belly of the omohyoid muscle.
carotid triangle, superior carotid trigone.
cephalic triangle one on the anteroposterior plane of the skull, between lines from the occiput to the forehead and to the chin, and from the chin to the forehead.
digastric triangle submandibular triangle.
Einthoven's triangle an imaginary equilateral triangle with the heart at its center, formed by the axes of the three bipolar limb leads.
triangle of elbow a triangular area on the front of the elbow, bounded by the brachioradial muscle on the outside and the round pronator muscle inside, with the base toward the humerus.
triangle of election superior carotid triangle.
facial triangle a triangular area whose points are the basion and the alveolar and nasal points.
femoral triangle the area formed superiorly by the inguinal ligament, laterally by the sartorius muscle, and medially by the adductor longus muscle; called also Scarpa's triangle.
infraclavicular triangle that formed by the clavicle above, the upper border of the greater pectoral muscle on the inside, and the anterior border of the deltoid muscle on the outside.
inguinal triangle the triangular area bounded by the inner edge of the sartorius muscle, the inguinal ligament, and the outer edge of the long adductor muscle.
lumbocostoabdominal triangle that lying between the external oblique muscle of the abdomen, the posterior inferior serratus muscle, the erector muscle of the spine, and the internal oblique muscle of the abdomen.
occipital triangle the area bounded by the sternocleidomastoid muscle in front, the trapezius muscle behind, and the omohyoid muscle below.
Scarpa's triangle femoral triangle.
subclavian triangle a triangular area bounded by the clavicle, the sternocleidomastoid muscle, and the omohyoid muscle.
suboccipital triangle that lying between the posterior greater rectus muscle of the head and the superior and inferior oblique muscles of the head.
an irregular area bounded by the serratus posterior inferior, obliquus externus, obliquus internus, and erector spinae muscles.
lum·bo·cos·to·ab·dom·i·nal tri·an·gle(lŭm'bō-kŏs'tō-ab-dom'i-năl trī'ang-gĕl)
An irregular area bounded by the serratus posterior inferior, obliquus externus, obliquus internus, and erector spinae muscles.
The triangle bounded in front by the obliquus abdominis externus, above by the lower border of the serratus posterior inferior and the point of the 12th rib, behind by the outer edge of the erector spinae, and below by the obliquus abdominis internus.
See also: triangle