After the neighbors heard about a rocket launched from a courtyard that broke a window, continued its flight into an apartment and set it on fire, we discussed how to protect ourselves. As someone said: Стрёмно! (It’s scary.)

С Новым годом! Happy New Year! Just like every other year, my neighbors and I are relieved that the holidays are almost over. The month from mid-December to mid-January is like living next to a shooting range or behind the front lines of a war — an almost constant barrage of fireworks that wake the newborn on the second floor, set off the Yorkshire Terrier on the fourth floor, and keep every other living soul awake and jumpy. Oh, for a good night’s sleep!

Стрёмно is a funny word. You won’t find it in any Soviet academic dictionaries or etymology reference books. In more recently published general dictionaries it is noted as вульг. (“vulgar,” i.e., low-class) and has larger entries in dictionaries of contemporary youth slang. So it seems like a slang word that appeared in the last 25 years or so.

So why, then, can you find it in literary works dating to the early 19th century? I’m not quite sure how that happened, but I did discover that its origins are in prison slang.

Стрём is both a look-out and the danger the look-out is looking out for. I suppose because the camp system was scattered across the country, you can hear the variations стрём, стрёма and стрёмя — all words that mean look-out, guard, or danger. Стрёмщик is someone on guard. Стрёмить is to scare or threaten someone.

Стрёмно covers a range of meanings: dangerous, frightening, weird or unpleasant. You can say стоять (literally to stand) or быть на стрёме or на стрёмках (to be on guard). This can be external guard duty: Вася, стоящий на стрёме, свистом предупреждает об опасности (Vasya stands on guard and whistles to warn of a danger.) Or: Вниз спустился, чтоб на стрёме быть. Мало ли что (I went downstairs to keep watch. You just never know.)

Or it can be an internal guard: У меня чуткий сон, как у собаки. Да тут любой на стрёме будет. (I’m a light sleeper, like a dog. But anyone would be on edge here.)

Or it can be what you shout when you spot danger: Иван научился также от Григория пугать мошенников и узнавать их в толпе; стоит только сказать: "стрёма!" (Ivan also learned from Grigory how to scare crooks and find them in the crowd — all he had to do was say, “Watch it!”)

That’s pretty much classical usage. Today you can say мне стрёмно! (I’m scared!) or я на стрёмках (I’m on guard) without sounding either too old-fashioned or like an oldster trying to sound young and hip.

Now if you are young and hip — or if you have the pleasure of raising or spending time with someone who is young and hip — you might hear стрёмно and related words used more to mean weird, wacko, or striking. Там стрёмная обстановка (The situation there is hinky). The adjective стрёмный can refer to a person who is dangerous, fearless, and powerful: Видишь этого стрёмного мужика? Это новый маринин муж. (See that guy over there — the ball-breaker? That’s Marina’s new husband.) Or it can be weird-cool: стрёмная стрижка (outta-here haircut). Or indecent-funny-cool, like стрёмный анекдот (wild joke).

Somehow it has also come to mean lack of desire: Мне стрёмно пойти на вечеринку (I don’t feel like going to the party.)

Of course, this is all for educational purposes. You don’t need to use стрёмно at all. Scared? Боюсь. (I’m scared.) Опасаюсь. (I’m anxious.) Мне тревожно. (I’m on edge.) Мне страшно. (I’m terrified.) У меня паника. (I’m panicking.) Меня трясёт. (I’m so scared I’m shaking.) Ноги подкосились. (My knees are quaking.)

That should cover pretty much everything, from a small spider to that scary dude Marina married.

Michele A. Berdy is a Moscow-based translator and interpreter, author of “The Russian Word’s Worth,” a collection of her columns. Follow her on Twitter @MicheleBerdy.