aggressive: (n. aggressiveness) Quick to fight or argue, or forceful in making efforts to succeed or win.
anesthesia: A medical treatment that causes a numbing or loss of physical feeling. Doctors can induce anesthesia in one area of the body (local anesthesia) or they can offer general anesthesia, where a patient temporarily loses consciousness.
bacteria: (singular: bacterium) Single-celled organisms. These dwell nearly everywhere on Earth, from the bottom of the sea to inside other living organisms (such as plants and animals). Bacteria are one of the three domains of life on Earth.
calcium: A chemical element and alkali metal common in minerals of the Earth’s crust and in sea salt. It is also found in bone mineral and teeth, and can play a role in the movement of certain substances into and out of cells.
correlation: A mutual relationship or connection between two variables. When there is a positive correlation, an increase in one variable is associated with an increase in the other. (For instance, scientists might correlate an increase in time spent watching TV with an increase in rates of obesity.) Where there is an inverse correlation, an increase in one value is associated with a drop in the other. (Scientists might correlate an increase in TV watching with a decrease in time spent exercising each week.) A correlation between two variables does not necessarily mean one is causing the other.
decay: The process (also called “rotting”) by which a dead plant or animal gradually breaks down as it is consumed by bacteria and other microbes.
dental: (adj.) Meaning related to teeth.
diet: (n.) The foods and liquids ingested by an animal to provide the nutrition it needs to grow and maintain health. Sometimes this is a specific food-intake plan.
enamel: The glossy, hard substance that covers a tooth.
ethics: (adj. ethical) A code of conduct for how people interact with others and their environment. To be ethical, people should treat others fairly, avoid cheating or dishonesty in any form and avoid taking or using more than their fair share of resources (which means, to avoid greed). Ethical behavior also would not put others at risk without alerting people to the dangers beforehand and having them choose to accept the potential risks. Experts who work in this field are known as ethicists.
factor: Something that plays a role in a particular condition or event; a contributor.
federal: Of or related to a country’s national government (not to any state or local government within that nation). For instance, the National Science Foundation and National Institutes of Health are both agencies of the U.S. federal government.
fluoride: A chemical, such as sodium fluoride, that contains the element fluorine. In small doses, fluorides can help prevent tooth decay.
genetic: Having to do with chromosomes, DNA and the genes contained within DNA. The field of science dealing with these biological instructions is known as genetics. People who work in this field are geneticists.
inflation: (in economics) A drop in the buying power of money over time (such that a loaf of bread that once cost 20 cents, for instance, may now cost $2.59).
intervention: Deliberate action taken to bring about some anticipated outcome. (in medicine) A planned effort to prevent or treat a disease or other condition relating to health or well-being.
IQ: Short for intelligence quotient. It’s a number representing a person’s reasoning ability. It’s determined by dividing a person’s score on a special test by his or her age, then multiplying by 100.
mineral: Crystal-forming substances that make up rock, such as quartz, apatite or various carbonates. Most rocks contain several different minerals mish-mashed together. A mineral usually is solid and stable at room temperatures and has a specific formula, or recipe (with atoms occurring in certain proportions) and a specific crystalline structure (meaning that its atoms are organized in regular three-dimensional patterns). (in physiology) The same chemicals that are needed by the body to make and feed tissues to maintain health.
pediatrician: A doctor who works in the field of medicine that has to do with children and especially child health.
phosphate: A chemical containing one atom of phosphorus and four atoms of oxygen. It is a component of bones, hard white tooth enamel, and some minerals such as apatite.
policies: Plans, stated guidelines or agreed-upon rules of action to apply in certain specific circumstances. For instance, a school could have a policy on when to permit snow days or how many excused absences it would allow a student in a given year.
politician: A person who runs for or holds elected office in a town or larger governing body. For politicians, governing people (or organizations) and wielding power within government is a profession (job).
population: (in biology) A group of individuals (belonging to the same species) that lives in a given area.
recruit: (noun) New member of a group or human trial. (verb) To enroll a new member into some group or organization. It could be into the military. Or it could be into participating in a research group to test some drug, behavior or environmental condition.
resident: Some member of a community of organisms that lives in a particular place. (Antonym: visitor)
risk: The chance or mathematical likelihood that some bad thing might happen. For instance, exposure to radiation poses a risk of cancer. Or the hazard — or peril — itself. (For instance: Among cancer risks that the people faced were radiation and drinking water tainted with arsenic.)
social: (adj.) Relating to gatherings of people; a term for animals (or people) that prefer to exist in groups. (noun) A gathering of people, for instance those who belong to a club or other organization, for the purpose of enjoying each other’s company.
toxicology: The branch of science that probes poisons and how they disrupt the health of people and other organisms. Scientists who work in this field are called toxicologists.