There are so many Hebrew expressions that either translate in a hilarious way, defy translation, or make little sense to English speakers. Eventually, however, you find yourself pining for those expressions, wishing they existed in English.
Al ha panim - "On the face" - really bad: "How was my presentation? On the face." (I have actually heard people translate that one literally).
Lishbor sheen-eye-im- "To break one's teeth" To work really hard at something: "I broke my teeth learning this language only to leave the country and never use it again." (ditto)
Lehicaness b'ivri - "To enter my veins" - To get on my nerves, like entering your blood supply (I think. I am not sure) "That right-wing columnist really gets in my veins.""
Mah Pitohm? - "What, suddenly?" - WTF? Getouttatown: "Now you say you don't like your job? What suddenly?" I have also heard parents admonish their kids for behaving badly (when presumably they had been behaving well before) by saying Mah Pitohm?
Sotziomat! - "Sociopath(?)" an expression from the army that indicates a selfish person who thinks there is an "I" in "Team". "Yossi did not once offer to carry the stretcher during training exercises. What a sotziomat!"
Lasim Zayin - "to put penis"- to endeavour, to try hard/be motivated (another army phrase) It also means to do pushups. "Dani, your uniform is a disgrace. Hit the floor and put penis."
Manyak "assohole" - not to be confused with (maniac, from where it probably derives). Usually begins with "Ya" "You cut me off again, ya'maniac."
Lezayen "to penis" to screw. It always bothered me that the colloquial term for sex is directly translated as "to penis". Years ago, a friend of my sister said that she wanted to start using "lenartek" or "to vagina" someone. Hmmmmm.
Words that I miss but don't translate: K'eeloo "ersatz" something that is trying to be something but is not the real thing. Ersatz is not quite it, and even if it were, I am not confident on how to pronounce it without sounding stupid or pompous. "that tang they served us at the hotel is k'eeloo orange juice."
Staaam this really has no translation. You say it when you are teasing someone, and they start to take offense. And you say: "staaam," meaning: I was just foolin' around. It can also be a way to dismiss the importance or gravity of a question: What did you do at Osnat's house. "We, staaam, just sat around and watched the news." The word staaam can also be a monosyllabic reply to just about anything: "Why did you do that:?" Staam.
Davka This one is really hard to explain, but it is a word to describe why you did something even though you weren't supposed to: "Why did you go to the party when you knew you would have a bad time?" Davka. "I am a peacenic, but I davka joined the army because I don't want our armed forces to be filled with only hawkish, trigger-happy, action-movie addicts."