The latest season of The Americans is wrapping up tonight, so it's time to make like deep-cover 1980s Soviet agents Philip and Elizabeth Jenkins, put on a wig, and take surveillance of these 10 spy and Cold War terms.

1. COLD WAR

Cold war originated as a general term for “a state of political tension and military rivalry between nations that stops short of full-scale war.” The first to use the phrase in print was George Orwell in 1945.

The Cold War between the U.S. and Soviet Union began sometime around the end of World War II (historians debate this point). During the Reagan and Carter eras, U.S.–Soviet relations deteriorated even further with the Soviet invasion of Afghanistan; mutual Olympic boycotts (in 1980 and 1984); the development of the Strategic Defense Initiative, derisively known as Star Wars; and the downing of Korean Airlines flight 007.  The Cold War ended with the dissolution of the Soviet Union in 1991.

2. ARPANET

Initially funded by the Advanced Research Projects Agency, or ARPA (later known as the Defense Advanced Research Projects Agency, or DARPA, birthplace of creepy robots), the ARPANET was one of the technical foundations of the Internet. In The Americans, Philip bugs the ARPANET to get information about America’s stealth technology.

3. EST

Like the Cold War, est was the epitome of the early 1980s. Standing for Erhard Seminars Training, est was founded in 1971 by “critical thinker” Werner Erhard. The seminars ran until 1984 and were a combination of Zen, Scientology, and Erhard’s contributions that was designed as a “human potential movement.”

Sandra, the wife of CIA agent Stan Beeman, is an est-devotee and eventually leaves her husband for an “est man.” Stan tries to become an est man himself, although without much success. It's not the first time est was on TV: A 1979 Mork & Mindy episode, “Mork Goes Erk,” parodies est with a pre-Late Night David Letterman as Ellsworth, an Erhard-like character.

4. ILLEGALS PROGRAM

The Illegals Program consisted of a ring of sleeper agents who were placed in the U.S. by the Russian Foreign Intelligence Service. In June 2010, 11 such agents were arrested.

As in The Americans, these spies were living in plain sight: They assumed American identities and did things like enroll in colleges, get jobs, and have kids, all with the goal of infiltrating policy making circles, according to The New York Times; the federal complaint about the spies' activities "read like an old-fashioned cold war thriller":

Spies swapping identical orange bags as they brushed past one another in a train station stairway. An identity borrowed from a dead Canadian, forged passports, messages sent by shortwave burst transmission or in invisible ink. A money cache buried for years in a field in upstate New York. ... [The illegals] also used cyber-age technology ... They embedded coded texts in ordinary-looking images posted on the Internet, and they communicated by having two agents with laptops containing special software pass casually as messages flashed between them.

The show’s creators have said these 2010 arrests were the inspiration for the show. Of course there are some major differences: The Americans takes place during the Cold War, while the real-life arrests were made during a “peaceful” time between the U.S. and Russia. Also, Philip and Elizabeth are much more active than real sleeper agents would ever be.

And in case you were wondering, the term sleeper for an agent originated in the mid-1950s in reference to Communist agents in the west.

5. KGB

KGB stands for Komitet gosudarstvennoy bezopasnosti, or the "Committee for State Security." The KGB was the Soviet Union’s main security agency from 1954 until 1991, and is often thought of as the Soviet counterpart to America's Central Intelligence Agency. However, the KGB was much bigger than the CIA, encompassing the equivalent of the CIA, the NSA, the Secret Service, parts of the FBI, and more.

6. RE-DOUBLED AGENT

If you think being a double agent is hard, try being a re-doubled agent. A double agent is a spy who’s actually spying for the other side. Nina Krilova, a KGB officer, is forced into being a double agent for CIA agent Beeman. After she confesses to spying for the Americans, she becomes a re-doubled agent—she spies on Beeman for the KGB while Beeman thinks she’s continuing to spy for him.

7. REFUSENIK

A refusenik was someone, especially a Jew, who was refused permission to emigrate from the Soviet Union. Jews faced a long history of persecution in Russia and the Soviet Union. During the Cold War, just requesting an exit visa was grounds for termination from jobs. One Jewish mathematician, Yosef Begun, applied to live in Israel, was fired from his job, convicted of being a “parasite” (the term for able-bodied people who didn’t work), and was sent to Siberia. Some refuseniks became defectors, like scientist Anton Baklanov on the show.

The word refusenik translates from the Russian otkaznik, originally meaning a “Jew who was refused permission to emigrate." In English by the early 1980s, a refusenik was someone who refused to do something as a form of protest.

The suffix -nik first appeared in English around 1945 and comes from the Yiddish and Russian -nik, meaning "person or thing associated with or involved in.” In English, -nik “rocketed to popularity,” as the Online Etymology Dictionary drolly puts it, with sputnik in the 1950s.

8. REZIDENTURA

Rezidentura is Russian lingo for the base of operations for resident spies. A resident spy is an agent operating in a foreign country for long stretches of time, and can be legal or illegal.

A legal resident spy might be an official KGB officer assigned “to supervise Soviet espionage in the States,” according to ThinkProgress, and because they have diplomatic immunity, would simply be expelled from the country if caught. A caught illegal resident would suffer a much harsher fate.

9. STEALTH TECHNOLOGY

Although militaries have been trying to hide themselves from the enemy since the dawn of time, modern stealth technology dates to the development of radar. Early attempts include when the U2 spy plane was coated in a special paint for secret missions over the Soviet Union. But it wasn’t referred to as “stealth” until more recently.

An archaic meaning of the word stealth is “to steal,” while the sense of “secret action” developed in the 14th century. The popularity of the word was in a steady decline from the early 1800s until the early 1980s when it jumped with the advent of the stealth fighter and stealth bomber.

10. VLADIMIR LENIN ALL-UNION PIONEER ORGANIZATION

The Vladimir Lenin All-Union Pioneer Organization was a kind of Soviet Girl and Boy Scouts of America.  Running from 1922 to 1991, it was in theory an honor for the best students, but almost all 10-15 year olds were members. They also had to take an oath that said:

I (name), joining the ranks of the All-Union Pioneer Organization named after Vladimir Ilich Lenin, solemnly swear before my comrades to love my Motherland dearly, live, study, and struggle in a manner bequeathed by the great Lenin and taught by the Communist Party, and to hold sacred the Laws of the Pioneers of the Soviet Union.

Nina fondly recalls her summers in Pioneer camp, especially her nifty Lenin-head pin.

BONUS: SECOND GENERATION ILLEGALS

“Last year the Centre started a program,” handler Claudia tells the Jenkins, “to develop offices they’re calling second generation illegals.”

Such illegal resident spies would be the American-born children of illegals, who with “legitimate” American identities would be able to infiltrate such government offices as the CIA and FBI.

While the Illegals Program was certainly real, could a second generation illegals program exist in real life? Probably not, Harvey Klehr, a professor at Emory and KGB expert, told ThinkProgress.

The KGB has twice tried to recruit the children of their agents—but those agents were legals—and once the son of American KGB couriers. However, soon after he was sent to Harvard on the KGB’s dime, another courier defected and gave up dozens of agents, including Harvard boy’s parents.

As for the children of illegals, the KGB expert says that kids in general can’t be trusted with “the kind of intel they’d need to know in order to be recruited in the first place,” and that they’d inevitably, if inadvertently, give up their parents.