tri ammonic three molecules (tri-am-mo'nik). of ammonium

Containing triangle (tri'an-gl). A three-cornered and three-sided figure, an area or space of three-cornered shape. anterior t. of the neck. The space bounded by the middle line of the neck, the anterior border of the sternocleidomastoid, and a line running along the lower border of the mandible and continued to the mastoid proce of the occipital bone, carotid t., inferior. The space bounded by the middle line of the neck, the sternomastoid and the anterior belly of the omohyoid muscle, carotid t., superior. The space bounded by the anterior belly of the omohyoid muscle, the posterior belly of the digastric us and the sternomastoid. cephalic t. A t. on the anteroposterior plane of the skull formed by lines joining the occiput and forehead and chin, and one uniting the two latter, facial t. A t. bounded by lines uniting the basion and the alveolar and nasal points and one uniting the two latter, femoral t. See Scarpa's t., under Scarpa, frontal t. A t. bounded by the maximum frontal diameter and lines joining its extremities and the glabella. He elbach's t. See He elbach. inferior carotid t. The space bounded by the middle line of the neck, the anterior border of the sternocleidomastoid, and the anterior belly of the omohyoid. inferior occipital t. Of Welcker, a t. having the bimastoid diameter for its base and the inion for its apex, inguinal t. See Scarpa's t., under Scarpa, lumbocosto-abdominal t. The space bounded in front by the obliquus abdominis extern us, above by the lower border of the serratus posticus inferior and the point of the twelfth rib, behind by the outer edge of the erector spinae, and below by the obliquus abdominis intern us. muscular t. See inferior carotid t. mylohyoid t. The triangular space formed by the mylohyoid muscle and the two bellies of the digastric muscle, occipital t. of the neck. The space bounded by the sternocleidomastoid, the trapezius, and the omohyoid, omoclavicular t. See subclavian t. omohyoid t. See superior carotid t.