| ORD | optical rotatory dispersion; oral radiation death |
|---|---|
| OROS | oral osmotic |
| ORT | object relations technique; operating room technician; oral rehydration therapy |
| OS | left eye [Lat. oculus sinister]; occipitosacral; occupational safety; office surgery; Omenn syndrome... |
| OSCC | oral squamous cell carcinoma |
| spinal part of arachnoid | That portion of the arachnoid which lies within the vertebral canal and surrounds the spinal cord and the vertebral portion of the subarachnoid space. It extends from the foramen magnum above to the S-2 vertebral level. Since the spinal cord ends at the L-2 vertebral level, a wide separation occurs between the arachnoid and pia mater, the lumbar cistern, filled with cerebrospinal fluid in which the cauda equina is suspended. Synonym: arachnoidea mater spinalis, spinal part of arachnoid. (05 Mar 2000) |
|---|---|
| spongy part of the male urethra | The portion of the male urethra, about 15 cm in length, which traverses the corpus spongiosum. Synonym: pars spongiosa urethrae masculinae, pars cavernosa, penile urethra, spongy part of the male urethra. (05 Mar 2000) |
| squamous part of frontal bone | The broad curved portion of the frontal bone forming the forehead. Synonym: squama frontalis. (05 Mar 2000) |
| squamous part of occipital bone | The tabular or squamous portion of occipital bone. Synonym: squama occipitalis, occipital squama, frontal squama. (05 Mar 2000) |
| squamous part of temporal bone | The broad, flat, thin (scale-like) anterior and superior portion of the temporal bone forming part of the lateral wall of the cranial vault. Synonym: pars squamosa ossis temporalis, squama temporalis, temporal squama. (05 Mar 2000) |
| nasal part of frontal bone | Nasal portion of the frontal bone which lies between the two orbital parts anteriorly and forms part of the roof of the nasal cavity. Synonym: pars nasalis ossis frontalis. (05 Mar 2000) |
| nasal part of pharynx | <anatomy> The portion of the pharynx extending from the posterior nares to the level of the soft palate. (27 Sep 1997) |
| sternal part of diaphragm | The small slip on each side that arises from the inner surface of the xiphoid process and inserts on the central tendon. Synonym: pars sternalis diaphragmatis. (05 Mar 2000) |
| sternocostal part of pectoralis major muscle | pars sternocostalis musculi pectoralis majoris, sternocostal head of pectoralis major |
| nervous part of retina | nervous part of retina |
| neural part of hypophysis | It is composed of the infundibulum and the nervous lobe of hypophysis. See: hypophysis. Synonym: lobus posterior hypophyseos, neural part of hypophysis, pars nervosa hypophyseos, posterior lobe of hypophysis. Origin: neuro-+ hypophysis (05 Mar 2000) |
| straight part of cricothyroid muscle | <anatomy> See: cricothyroid muscle. (05 Mar 2000) |
| subcutaneous part of external anal sphincter | pars subcutanea musculi sphincteri ani externi, subcutaneous portion of external anal sphincter |
| sublenticular part of internal capsule | The part of the internal capsule below the caudal third of the lentiform nucleus that contains the auditory radiation as well as that part of the optic radiation representing the upper part of the contralateral half of the binocular visual field. Synonym: pars sublentiformis capsulae internae, sublenticular limb of internal capsule. (05 Mar 2000) |
| suboccipital part of vertebral artery | <anatomy, artery> Paired arteries which supply the muscles of the neck, spinal cord and cerebellum. (27 Sep 1997) |