What are some important or interesting vocabulary words in the book Between Shades of Gray?

In Between Shades of Gray, Ruta Sepetys offers a fictional account of Lithuanian history in the 1930s–1940s, when the country was made a Soviet Republic.
One of the first important words that arises is “NKVD,” the initials in Russian of the Soviet secret police: People's Commissariat for Internal Affairs, or Narodnyy Komissariat Vnutrennikh Del. In Chapter 1, several NKVD officers arrive at the home of Lina, the 15-year-old protagonist, and her family. They are there to arrest and deport them.
When her mother stalls for time and calculates what items might be useful to pack, she puts on a fancy hat. One of the officers mocks her for being one of the “bourgeois pigs.” “Bourgeois,” a French word commonly used in English and other languages, is derived from the French word for town and literally means an urban dweller, as contrasted to a rural person. The word "bourgeoisie" came to mean the middle and upper classes, composed of people such as lawyers, doctors, and teachers. In Soviet revolutionary interpretation of Karl Marx’s works, it refers to those who uphold traditional values (and their symbols, such as luxury goods) and oppose the goals of the revolution.
Lina recalls a conversation between her father and some friends from the university, in which they asked her opinion of the new political arrangement that was the Soviet “annexation.” While an “annex” can literally be an addition to a building, in this usage, it means “takeover.” In 1940, the Soviet army had invaded Lithuania and declared the formerly independent republic to be part of the Soviet Union.
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