sacral (SAK-răl, SĀ-krăl): Pertaining to the sacrum.

sagittal plane (SĂJ-ĭ-tăl plān): Plane that divides the body or an organ vertically into left and right sides.

salpingectomy (sal-pĭn-JEK-tŏ-mē): Excision of the uterine/fallopian tube.

salpingitis (săl-pĭn-JĪ-tĭs): Inflammation of a fallopian/uterine tube.

salpingo-oophorectomy (săl-pĭng-gō-ō-ŏf-ō-RĔK-tō-mē): Excision of the uterine tube and ovary.

salpingostomy (săl-pĭng-ŎS-tō-mē): Creation of an artificial opening in the uterine tube.

sarcopenia (săr-kō-PĒN-ē-ă): Abnormal reduction of connective tissue.

satellite cell (SĂT-l-īt sel): Glial cell type in the PNS that provides support for neurons in the ganglia.

scar (skăr): Collagen-rich skin formed after the process of wound healing that differs from normal skin. Also known as a cicatrix.

Schwann cell (shvon sel): Glial cell type in the PNS that provides the myelin insulation for axons in nerves.

sclerokeratitis (sklĕr-ō-kĕr-ă-TĪ-tĭs): Inflammation of the sclera and cornea.

scleromalacia (sklĕ-rō-mā-LĀ-sē-ă): Softening of the sclera.

sclerotomy (sklĕ-ROT-ŏ-mē): Incision into the sclera.

scoliosis (skō-lē-Ō-sĭs): Abnormal condition of (lateral) curved spine.

scrotum (SKRŌ-tŭm): External pouch of skin and muscle that houses the testes.

sebaceous gland (sē-BĀ-shŭs gland): Type of oil gland that is found all over the body and helps to lubricate and waterproof the skin and hair.

seborrhea (sĕb-or-Ē-ă): Discharge (excessive) of sebum.

secondary adaptive response (SĔK-ŏn-dăr-ē ad-ap-TĬV ri-SPONS): Immune response observed upon re-exposure to a pathogen, which is stronger and faster than a primary response.

secondary lymphoid organs (SĔK-ŏn-dăr-ē LIM-foyd OR-găn): Sites where lymphocytes mount adaptive immune responses, examples include lymph nodes and spleen.

semen (SĒ-mĕn): Ejaculatory fluid composed of sperm and secretions from the seminal vesicles, prostate, and bulbourethral glands.

seminal vesicle (SĔM-ĭ-năl VES-ĭ-kĕl): Gland that produces seminal fluid, which contributes to semen.

seminiferous tubules (sĕm-ĭn-ĬF-ĕr-ŭs TŪ-būls): Tube structures within the testes where spermatogenesis occurs.

sensation (sen-SĀ-shŏn): Nervous system function that receives information from the environment and translates it into the electrical signals of nervous tissue.

sepsis (SEP-sĭs): Toxic condition due to spread of bacteria or their toxins from an infection.

septal cartilage (SEP-tŭm KART-ĭ-lăj): The flexible portion you can touch with your fingers.

septoplasty (sĕp-tō-PLĂS-tē): Surgical repair of the septum.

septotomy (sĕp-TŎT-ō-mē): Incision into the (nasal) septum.

seroconversion: The reciprocal relationship between virus levels in the blood and antibody levels. As the antibody levels rise, the virus levels decline, and this is a sign that the immune response is being at least partially effective (partially, because in many diseases, seroconversion does not necessarily mean a patient is getting well).

serous (SĒR-ŭs): You may recall that serous membranes throughout the body are folded back on themselves, which results in a double-layered membrane separated by serous fluid. The serous membrane surrounding the lungs is called pleura. The serous membrane surrounding the abdominopelvic organs is called peritoneum.

serous membrane (serosa) (SĒR-ŭs MEM-brān): Epithelial membrane composed of mesodermally derived epithelium (mesothelium) that is supported by connective tissue.

serous space (SĒR-ŭs spās): Thin, fluid-filled space between the parietal and visceral layers of the serous membrane.

Sertoli cells (SERT-ŏ-lē sels): Cells that support germ cells through the process of spermatogenesis; a type of sustentacular cell.

severe combined immunodeficiency disease (scid): Genetic mutation that affects both t cell and b cell arms of the immune response.

sexually transmitted disease (STD) (SEKS-ū-ă-lē trăns-MĬT-ed diz-ĒZ): Infection spread through sexual contact.

sialolith (sī-AL-ŏ-lith): Stone in the salivary gland.

sickle cell disease: A genetic disorder involving the production of an abnormal type of hemoglobin which delivers less oxygen to tissues and causes erythrocytes to assume a sickle (or crescent) shape.

sidestream smoke (SĪD-strēm smōk): Some that is given off by the burning cigarette.

sigmoidoscopy (sig-moy-DOS-kŏ-pē): Process of viewing the sigmoid colon.

silent mis: A myocardial infarction without symptoms. The patient may not know that they are having an MI

sinus rhythm (SĪ-nŭs Rith-ĭm): This is the rhythm set by the heart’s pacemaker, the sinoatrial node and is usually approximately 60-90 beats per minute in a resting adult

sinusitis (sī-nŭs-Ī-tĭs): Inflammation of a sinus.

skeletal muscle (SKEL-ĕt-ŏn MŬS-ĕl): Skeletal muscles are responsible for voluntary muscle movement.

sleep apnea (slēp ap-NĒ-ă): Chronic condition characterized by the cessation of breathing during sleep.

smooth muscle (MŬS-ĕl): Smooth muscle is mainly associated with the walls of internal organs. Smooth muscles are responsible for involuntary muscle movement.

soft palate (soft PAL-ăt): The soft palate is located at the posterior portion of the nasal cavity and consists of muscle tissue.

solutes (SOL-ūt): The minor component in a solution.

soma (SŌ-mă): In neurons, that portion of the cell that contains the nucleus; the cell body, as opposed to the cell processes (axons and dendrites).

somatic nervous system (SNS) (sō-MAT-ik NĔR-vŭs SIS-tĕm): Functional division of the nervous system that is concerned with conscious perception, voluntary movement, and skeletal muscle reflexes.

sonogram (SON-ŏ-gram): The record of sound.

sonography (sō-NOG-ră-fē): Process of recording sound.

sonohysteropgraphy (SHG) (sō-nō-his-tĕ-ROG-ră-fē): Process of recording the uterus by use of sound.

speculum (SPEK-yŭ-lŭm): Instrument for opening a body cavity to allow visual inspection.

sperm (pl; spermatozoa) (spĕrm (pl; spĕr-măt-ō-ZŌ-ă): Male gamete.

spermatic cord (spĕr-MĂT-ĭk kord): Bundle of nerves and blood vessels that supplies the testes; contains ductus deferens.

spermatid (SPĔR-mă-tĭd): Immature sperm cells produced by meiosis II of secondary spermatocytes.

spermatocele (spĕr-MĂT-ō-sēl): Distention of the epididymis containing an abnormal cyst-like collection of fluid and sperm cells.

spermatocyte (spĕr-MĂT-ō-sīt): Cell that results from the division of spermatogonium and undergoes meiosis I and meiosis II to form spermatids.

spermatogenesis (spĕr-măt-ō-JĔN-ĕ-sĭs): Formation of new sperm, occurs in the seminiferous tubules of the testes.

spermatogonia (spĕr-măt-ō-GŌ-nēa): Diploid precursor cells that become sperm (singular = spermatogonium).

spermatolysis (spĕr-măt-ŎL-ĭ-sĭs): Dissolution (destruction) of sperm.

spermiogenesis (spĕr-mē-ō-JĔN-ĕ-sĭs): Transformation of spermatids to spermatozoa during spermatogenesis.

sphincter (SFĬNK-tĕr): A circular muscle constricting an orifice.

spinal cord (SPĪ-năl kord): Organ of the central nervous system found within the vertebral cavity and connected with the periphery through spinal nerves; mediates reflex behaviors.

spleen (splēn): Secondary lymphoid organ that filters pathogens from the blood (white pulp) and removes degenerating or damaged blood cells (red pulp).

splenectomy (splē-NEK-tŏ-mē): Excision of the spleen,

splenomegaly (splē-nō-mē-GĀ-lē): Enlarged spleen.

splenopexy (SPLĒ-nō-pĕk-sē): Surgical fixation of the spleen.

sphygmomanometer (sfĭg-mō-măn-ŎM-ĕt-ĕr): Instrument used to measure blood pressure.

spirometer (spī-Rŏm-ĕt-ĕr): Instrument used to measure breathing (lung volume).

spirometry (spī-RŎM-ĕ-trē): Measuring breathing (air flow).

spondylarthritis (spon-dil-ar-THRĪT-ĭs): Inflammation of the vertebra and joint.

spondylosis (spŏn-dĭ-LŌ-sĭs): Abnormal condition of the vertebrae.

sprain (sprān): Injury to a joint whereby a ligament is stretched or torn.

sputum (SPŪT-ŭm): Mucous secretion from lungs, bronchi, and trachea that is expelled through the mouth.

squamous cell carcinoma (SKWĀ-mŭs sel kar-sĭn-Ō-mă): Cancer that affects the deratinocytes of the stratum spinosum and presents as lesions commonly found on the scalp, ears, and hands.

stapedectomy (stā-pĕ-DEK-tŏ-mē): Excision of the stapes.

staphylococcus (staf-ĭ-lō-KOK-ŭs): Berry-shaped bacterium in grapelike clusters.

Staphylococcus aureus (staf-ĭ-lō-KOK-ŭs): Staphylococcus aureus is a bacterium that is commonly found in minor skin infections, as well as in the nose of some healthy people.

steatohepatitis (stē-ăt-ŏ-hep-ă-TĪT-ĭs): Inflammation of the liver associated with fat.

steatorrhea (stē-ă-tō-RĒ-ă): Discharge of fat.

steatosis (stē-ă-TŌ-sĭs): Abnormal condition of fat.

sterility (stĕ-RIL-ĭt-ē): A condition of being unable to conceive or reproduce the species.

sterilization (ster-ĭ-lĭ-ZĀ-shŏn): Procedure that prevents pregnancy, either a female’s ability to conceive or a male’s ability to induce conception.

sternoclavicular (stĕr-nō-klă-VĬK-ū-lăr): Pertaining to the sternum and clavicle.

sternoid (STĔR-noyd): Resembling the sternum.

stethoscope (STETH-ŏ-skōp): Instrument used to hear internal body sounds.

stillborn (STIL-bōrn): An infant that is born dead.

stimulus (STĬM-ū-lŭs): An event in the external or internal environment that registers as activity in a sensory neuron.

stoma (STŌ-mă): Surgical opening between an organ and the surface of the body.

stomatitis (stō-mă-TĪT-ĭs): Inflammation of the mouth.

stomatogastric (stō-mă-tō-GĂS-trĭk): Pertaining to the mouth and stomach.

strain (strān): Injury to a muscle whereby a tendon is stretched or torn.

stratified squamous epithelium (STRĂT-ĭ-fīd SKWĀ-mŭs ep-i-THĒ-lē-ŭm): Cells arranged in layers upon a basal membrane.

stratum basale (STRĀ-tŭm BĀS-al): Deepest layer of the epidermal.

streptococcus (strep-tŏ-KOK-ŭs): Berry-shaped bacterium in twisted chains.

stricture (STRIK-chŭr): Abnormal narrowing.

stroke (strōk): Loss of neurological function caused by an interruption of blood flow to a region of the central nervous system.

sty (stī): Infection of an oil gland of the eyelid (hordeolum).

stye (stī): Acute infection of eyelash hair follicle.

subarachnoid space (sŭb-ă-RAK-noyd spās): Space between the arachnoid mater and pia mater that contains CSF and the fibrous connections of the arachnoid trabeculae.

subcostal (sŭb-KOS-tăl): Pertaining to below the ribs.

subcutaneous (sŭb-kū-TĀ-nē-ŭs): Pertaining to under the skin.

subdural (sŭb-DŪ-răl): Pertaining to below the dura mater.

subdural hematoma (sŭb-DŪ-răl hĕm-ă-TŌ-mă): Tumor filled with blood pertaining to below the dura mater.

sublingual (sŭb-LING-gwăl): Pertaining to under the tongue.

submandibular (sŭb-măn-DĬB-ū-lăr): Pertaining to under the mandible.

submaxillary (sŭb-MĂK-sĭ-lĕr-ē): Pertaining to under the maxilla.

subscapular (sŭb-SKĂP-ū-lăr): Pertaining to below the scapula.

substernal (sŭb-STĔR-năl): Pertaining to below the sternum.

subungual (sŭb-ŬNG-gwăl): Pertaining to under the nail.

suffix: A word part added to the end of a word that changes the meaning of the word root.

sulcus/sulci (SŬL-kŭs/ SŬL-kī): Groove formed by convolutions in the surface of the cerebral cortex; see fissure.

superficial (SOO-pĕr-FISH-ăl): Describes a position closer to the surface of the body.

superficial lymphatics (soo-pĕr-FĬSH-ăl lim-FAT-iks): Lymphatic vessels of the subcutaneous tissues of the skin.

superior (or cranial) (soo-PĒ-rē-or): Describes a position above or higher than another part of the body proper.

superior vena cava (soo-PĒ-rē-or VĒ-nă KĀ-vă): One of the two largest veins in the body. It carries deoxygenated blood from the head and upper extremities back to the heart.

suprapatellar (soo-pră-pă-TĔL-ăr): Pertaining to above the knee cap.

suture (SOO-chŭr): To stitch the edges of a wound.

sympathetic (sĭm-pă-THĔT-ĭk): Flight or fight response.

sympathetic nervous system (sĭm-pă-THĔT-ĭk NĔR-vŭs SIS-tĕm): Part of the nervous system that serves to accelerate heart rate, constrict blood vessels and raise blood pressure in response to stress. Responsible for fight or flight responses.

synapse (SĬN-ăps): Narrow junction across which a chemical signal passes from neuron to the next, initiating a new electrical signal in the target cell.

synaptic end bulb (sĭ-NĂP-tĭk ende bŭlb): Swelling at the end of an axon where neurotransmitter molecules are released onto a target cell across a synapse.

synarthrosis (sĭn-ăr-THRŌ-sĭs): Joints with no movements.

syncope (SING-kŏ-pē): Fainting.

syndrome (SĬN-drōm): Run together (signs and symptoms occur together characterizing of a specific disorder).

synovectomy (sĭn-ō-VĔK-tō-mē): Excision of the synovial membrane.

synovial membrane (sĭn-Ō-vē-ăl MEM-brān): Connective tissue membrane that lines the cavity of a freely movable joint.

synoviosarcoma (sĭn-ō-vē-Ō-mă-sar-KŌ-mă): Malignant tumor of the synovial membrane.

synthesis (Sĭn-thĕs-ĭs): The production of chemical compounds by reaction from simpler materials.

syphilis (SIF-ĭ-lĭs): A chronic bacterial disease spread primarily through sexual intercourse, but also congenitally by infection of a developing fetus. Rapidly spreads through the body and if left untreated becomes systemic.

systemic lupus erythematosus (sĭs-tĕm′ĭk loo′pŭs): Autoimmune disease in which the immune system recognizes its own cell antigens as being “non-self” and mounts an immune response against them. As a result, many body tissues and vital organs become chronically inflamed and damaged.

systole (SIS-tŏ-lē): Phase in cardiac cycle when ventricles contract and eject blood.

systolic pressure (SIS-tŏ-lik): The systolic pressure is the higher value (typically around 120 mm Hg) and reflects the arterial pressure resulting from the ejection of blood during ventricular contraction, or systole.