The coronavirus pandemic is putting words in the mouths of billions of people worldwide. Ventilator, BiPap, face coverings, homemade masks, PPE. These words are quickly becoming part of our daily terminology as the disease COVID-19, which has now killed more than 74,000 people around the globe, continues to spread.

Educating yourself on the science and the social responses will help you understand the situation and help explain it to others. If you know them all, well done on being so thoroughly informed. If not, this guide will help you brush up on the ever-changing lexicon you need to get along in a coronavirus world. We'll continue to update this story as our social response to the virus evolves. 

Novel coronavirus and SARS-CoV-2

No, the virus known to have infected over 400,000 people isn't actually named "coronavirus." The word refers to any in a family of viruses whose structure presents crownlike spikes when seen under a microscope. The term "novel coronavirus" is a general term for the current type we're fighting. It became a fixture before the virus was given an official name: SARS-CoV-2.

COVID-19

You may be tempted to use COVID-19 as a synonym for coronavirus, but that will confuse matters. COVID-19 is the name of the disease that the novel coronavirus causes. It stands for "coronavirus disease 2019."

The disease brings on flulike symptoms, but dangerously affects the lungs by filling them with fluid at a rapid rate. Patients with extreme cases may need respirators and oxygen to help them breathe, often for weeks. The fear is that fatalities will occur when patient need for ventilators outstrips the supply.

Nonmedical masks and face coverings

The Centers for Disease Control and Prevention, the US authority on health policy related to infectious diseases, has issued a recommendation for people to voluntarily wear face coverings in public when staying six feet from others outside your household is not an option.

The key takeaway is that the material you're using to cover your nose and mouth is not a medical-grade mask needed by public health care workers. Face coverings can be made in a number of styles from materials like cotton, a laundered t-shirt or a bandana. Here's everything you need to know about coronavirus prevention and homemade masks, and a resource guide on how to make your own face covering or mask.

N95 and surgical face masks

COVID-19 is a respiratory illness, and coronavirus spreads through vaporized droplets. N95 respirator masks are the type most proven to protect you from acquiring SARS-CoV-2. Other varieties, including surgical masks and homemade, are not proven to be effective at blocking the smallest particles that could carry the virus, which can remain in the air for up to 30 minutes. 

Homemade coverings (above) are regarded as effective at protecting other people from large droplets ejected through coughing and sneezing. If you have N95 or surgical masks at home, the medical community is asking for donations to help curb the shortage of masks.

Ventilators

A ventilator is a machine that helps a person breathe by expanding their lungs and supplying them with oxygen when it's too difficult to do so on their own. As the COVID-19 disease hospitalizes tens of thousands of people around the world, ventilators are critically low, and doctors are increasingly forced to decide which patients will receive their aid, and which will not. This is why ventilators are pivotal in the battle against COVID-19.

BiPap machine

A BiPap machine is a type of ventilator that some hospitals are using, or considering using, to help COVID-19 patients breathe. BiPap is short for bilevel positive airway pressure, and is similar to CPAP, or continuous positive airway pressure. These machines are commonly used for conditions like obstructive sleep apnea and pneumonia. If effective, they could potentially be used to treat more patients in need of ventilator support.

At-home coronavirus tests

Tests kits for COVID-19 that you can administer at home are being explored by the medical community and the FDA. The benefit of being able to find out if you acquired the virus without leaving the house -- potentially exposing others or yourself -- is appealing. Direct-to-consumer testing kits aren't authorized by the FDA at this point, however, and some fear that tests resulting in false negative results could endanger healthy people if the test-taker is actually positive for SARS-CoV-2. 

PPE

Personal protective equipment, or PPE, refers to any gear necessary to minimize a person's exposure to harmful materials that could cause illness or injury -- gloves, full body suits, protective eyewear and so forth. In the case of the coronavirus pandemic, N95 masks for health care workers are in critically short supply.

Zoonotic disease

Coronaviruses are transmitted between humans and animals -- that's the "zoo" in "zoonotic." It's believed that the virus originated in a shoehorn bat before being transmitted to another animal, and then to humans. The SARS-CoV-2 virus can be transmitted to some individual animals -- like a tiger at the Bronx zoo in New York -- through direct contact with an infected human. Domestic pets are not currently considered reservoirs to widely spread the disease, however. Other zoonotic diseases include anthrax, rabies, Lyme disease, H1N1 ("swine flu"), West Nile virus, salmonella and malaria. 

WHO

The World Health Organization, often called WHO, is the global body that's become a clearinghouse of information, research and safety guidelines. SARS-CoV-2, then referred to simply as novel coronavirus, was first reported to the WHO on Dec. 31, 2019, days after the first patients were hospitalized in the Chinese city of Wuhan.

PCR testing

A testing protocol to identify if you've contracted the SARS-CoV-2 coronavirus. This test works by identifying the virus' DNA through a process called PCR, or polymerase chain reaction. The PCR test looks for telltale markers distinct to this viral strain. The sample can be obtained through a throat or nasal swab, which makes it ideal for the kind of drive-through testing centers proposed in countries like the US. More details about coronavirus testing here.

Positive versus presumptive cases

How do you know if you're infected with the new coronavirus? Listing your symptoms isn't enough. Positive, or confirmed, cases are identified with lab tests. Presumptive cases are not. If you're exhibiting symptoms consistent with COVID-19 -- including fever, a dry cough and fluid accumulation in the lungs -- and have had contact with a confirmed case, you're still considered presumptive.

Community spread

SARS-CoV-2 is highly contagious, spreading through "respiratory droplets" (a cough, sneeze, transfer of saliva) and contaminated objects, like a door handle or other shared surfaces. Person-to-person spread means you can trace how the disease got from one person to another through direct contact, like shaking hands. Community spread refers to people in the same location contracting the virus without an obvious chain of events.

Community spread is an early sign that a disease can rapidly affect local, even global, populations. Read more at the Centers for Disease Control and Prevention.

Social distancing

In addition to thorough hand-washing, the WHO and CDC recommend the practice of social distancing to slow the spread of COVID-19 by keeping at least six feet away from others, refraining from touching and by staying indoors, especially if you're over 60, immunocompromised or suffering from an underlying condition. Local and national governments have responded by limiting gatherings of people, ranging from no more than 10 people to 50 or 250 or even 1,000.

Self-quarantine, self-isolation

People who largely stay inside their own home, hotel room or other space are said to self-quarantine or self-isolate. For example, many governments are asking travelers returning from afflicted areas to self-quarantine for two weeks. However, there's a technical difference. Quarantine refers to people who appear healthy, but could be at risk for exposure or infection. Isolation refers to separating positive or presumptive cases (see above) from the healthy population.

Mitigation, not containment

This phrase acknowledges that at pandemic proportions, nations can't contain the spread of coronavirus. But with social distancing, self-quarantine and isolation, the burden of COVID-19 can be mitigated. In other words, slowing down the rate of infection can increase chances of survival by avoiding overcrowding hospitals, running short on pivotal supplies before they can be replenished and overworking medical staff. This is a deeply sobering account of what happens when the COVID-19 disease overwhelms medical and support systems.

Pandemic versus epidemic

WHO officially declared the coronavirus SARS-CoV-2 a pandemic on March 11. The word "pan" (which roughly means "all") refers to the global nature of the spread, affecting virtually every country and region around the globe. An epidemic refers to a more localized region. Before reaching places like the US, coronavirus was considered an epidemic in China's Hubei province, and then in the country itself. Here's more on pandemics versus epidemics. 

Flatten the curve

Without mitigation, social distancing and all the rest, epidemiologists and other health experts predict a sharp increase in COVID-19 cases that looks like a tall, narrow spike on a graph. By following guidelines, the projected model looks shorter and spread out over time. The curve is flatter, milder, less pronounced. The hope of flattening the curve is to reduce fatalities by buying hospitals time to treat and scientists time to discover therapies and create a vaccine. 

Shelter in place

On March 16, six counties in the San Francisco Bay Area ordered residents to "shelter in place," a directive aimed at keeping people in their homes for three weeks, with the order widened to the whole state a few days later. It's now being implemented around the world. All nonessential businesses are shuttered, and with the exception of shopping for items like groceries and pharmaceuticals, picking up food and taking walks while maintaining a distance of six feet from others, locals are expected to stay inside. It's a fairly strict measure aimed at curbing community spread.

Read more: Where can you go in coronavirus lockdown? This is what you can and can't do

An abundance of caution

The preemptive closure of offices, businesses and schools ahead of positive cases has often been met with the phrase "due to an (over)abundance of caution." 

70% isopropyl alcohol

Washing thoroughly with soap and water is the best way to kill the coronavirus on the skin, but surfaces can be harder to disinfect. Experts say that disinfectant wipes and spray, and solutions made with 70% isopropyl alcohol are also effective at destroying the virus' structure. But be careful. Making your own hand sanitizer and other cleaning agents can be dangerous, and isn't recommended.

Stay informed on coronavirus updates and developments, help your friends and neighbors dispel myths about the virus and use these 10 practical tips to avoid coronavirus when you need to leave the house.