Glossary 641 



Sprain: Injury to the muscles, ligaments, or nerves about a joint; caused 

 by the joint being turned too far or in the wrong direction. 



Spring: A hole in the ground or a crevice in a rock from which water 

 flows naturally. 



Sputum (spu'ttim) : Spit. 



Stability (std-bil'i-ti) : Capacity to stay upright or to recover an up- 

 right position. 



Standard time : The time that has been established by law over a region 

 or country. 



Star: A great, blazing sun. 



{Starch: A most important food substance composed of carbon, oxygen, 

 and hydrogen chemically combined. 



Static electricity (stat'ik) : Stationary electricity. 



Steam: The invisible vapor into which water is changed by boiling. 



Steam engine : An engine in which steam is admitted alternately to oppo- 

 site sides of a piston in a cylinder, its expansion serving to drive the 

 piston back and forth. 



Steapsin (ste-ap'sin) : A ferment in pancreatic juice which helps digest 

 fat. 



Sterilize : To free from bacteria. 



Sternum: The breastbone. 



Stewing: Cooking in simmering hot water over a slow fire for a num- 

 ber of hours. 



Stimulant (stim'u-lant) : A substance capable of acting on the nervous 

 system, causing increased activity of the organs it controls. Tea and 

 coffee are stimulants. 



Stimulus (stim'u-lMs) : Anything that arouses the activity of an organ 

 or tissue. 



Stipules (stip'ulz) : A pair of leaf -like parts situated at the base of some 

 leaf stalks. 



Stomach: A pear-shaped pouch in the digestive tract. 



Stomata (sto'md-td) : Openings in the lower surfaces of leaves for the 

 admission of oxygen. 



Storage battery: A collection of storage cells. 



Storage cell: A device for storing up electrical energy in the form of 

 chemical energy. 



Strain: A muscle injury usually caused by efforts to lift too heavy loads. 



Strata (stra'td) : Layers; natural rock layers. 



Stratus (stra'ts) : Low, horizontal layers of clouds. 



Streamlined body : A body, such as the hull of a ship or the body of an 

 airplane, which is designed to pass through the air or water with only 

 a small amount of resistance. 



Structure : The way in which anything is built ; the parts of which it is 

 composed. 



Sublingual glands (sub-lm'gwal) : The pair of salivary glands lying 

 under the sides of the tongue. 



Submarine: A vessel designed to travel both above and below the sur- 

 face of the water. 



Submaxillary glands (sub-mak'si-la-ri) : The pair of salivary glands 

 lying just beneath the angles of the lower jaw at each side. 



Substance: Matter of any kind. 



Suffocation: Inability to breathe. 



Sulphates (sul'fatz) : Mineral substances composed mainly of sulphur 

 and oxygen ; needed by the body to make protoplasm, bones, and teeth. 



Sulphur: A solid, yellow, non-metallic substance. One of the elements. 



