“The Iranians’ strategy is clear,” a friend said to me a day or two before the American attack on Fordow. “They plan to deprive us all of sleep until we’re forced to surrender.”

Israelis have indeed been sleep-deprived, many having had to run to shelters once or more every night since Israel launched its air offensive against Iran. The lucky ones had mamadim to run to. The next most fortunate have had mamakim. Others had only mamamim or mamatsim, while those with none of the above had to make do with a merḥav mugan.

Readers of Mosaic may wonder about these terms. Let’s start with merḥav mugan. This means “protected space” in Hebrew and refers to any indoor area, such as a staircase or the lobby of a building, that is far from windows and not directly exposed to shrapnel and shockwaves from explosions. A merḥav mugan will not protect you from a ballistic missile landing on your roof, but it’s better to be in one than just at home or out in the open when missiles are falling.

Merḥav mugan is linguistically present in the mamad, the mamak, the mamam, and the mamats, all of which are acronyms (that is, abbreviations formed from the first letters of their component words) of which it is the main element. In the case of mamad, these words are merḥav mugan dirati, an “an apartmental protected space.” A mamad has been a mandatory feature of every private dwelling unit built in Israel since 1992, a result of the 1990 Gulf War, in which long-range missiles fell on Israel for the first time. As required by a 1992 law, every new or renovated such a unit in Israel must have a shelter with at least nine square meters of space, reinforced concrete walls, and blast-resistant steel doors and windows. Because there is no prohibition on using a mamad for other purposes in peacetime, Israelis routinely convert theirs into a bedroom, workroom, or storeroom and then frantically clear it out to make room for their families when military action looms.

A mamad is a good thing to have: you needn’t leave home to get to it and you can get to it quickly, well within the minute to minute-and-a-half between the time Israel’s Home Front Command sounds a siren on your smartphone and the time a missile lands. (In the current war with Iran, which saw heavier missiles covering greater distances than those previously launched from Gaza or Lebanon, Israelis also received advance phone warnings to prepare for a siren.)  When the threat is over, another smartphone message sounds the all-clear.

Yet an estimated 60 percent of Israelis live in homes built before 1992 that do not have a mamad. Many living in apartment buildings have a mamak, a merḥav mugan komati or “floor-wide protected space,” into which all the families living on the same floor can fit. For those with no mamak, either, there may be in the vicinity the separate structure of a mamats, a merḥav mugan tsiburi or “public protected space,” or else a mamam, a merḥav mugan mosadi or “institutional protected space” in a public building of some kind. Often known simply as miklatim or “shelters,” the mamak and mamam are large, generally underground spaces that can accommodate hundreds of people—who, however, have to get to them on time.

Hebrew loves acronyms—or as it calls them, roshey tevot, “word headings.” It may indeed have been their worldwide pioneer, its use of them having been facilitated by the fact that, a language written without vowels, it can insert these where and as it pleases to make any combination of consonants pronounceable. Still common words like Tanakh (an acronym of torah, n’vi’im, k’tuvim, “Pentateuch, Prophets, Writings”—that is, the Bible) and ḥazal (ḥakhameynu zikhronam li-vrakhah, “Our sages, may their memory be a blessing”—i.e., the rabbis of the Mishnah and the Talmud) go back to the early centuries of the Common Era. Like all Hebrew acronyms to this day, such abbreviated forms are indicated by the insertion of a quotation mark-like sign between their last and next-to-last letters. Thus, ḥazal is spelled חז”ל and tanakh is spelled תנ”ך, just as mamad is ממ”ד and mamak is ממ”ק.

It is only in the rabbinic literature of the late Middle Ages and afterwards, though, that the Hebrew acronym came fully into its own—so much so that, in turning to a page of rabbinic commentary or responsa from this period, one may be confronted by an unnavigable acronymic sea in which roshey tevot seem to outnumber actual words. Rabbi Avraham Yitzhak Yonah Stern, in the preface to his Sefer Roshey Tevot, a dictionary of Hebrew acronyms published in 1926, wrote in explaining the need for such a volume:

The shorthand of roshey tevot is an ancient custom among our rabbis, designed to maximize the time available for study and teaching by streamlining the time devoted to writing. Hence, Hebrew acronyms have proliferated to the point that, understandably, even those well-versed in them encounter ones they cannot decipher.

A glance at the first page of Stern’s dictionary reveals such acronyms as אאאומ”ר (el erekh apaiym u-maley raḥamim—“God the long-suffering and compassionate”), while on its last page you can find תש”ת (t’kiyah, sh’varim, tru’ah—the three shofar blowings of Rosh Hashanah) and תשומע”ט (t’shuvah u-ma’asim tovim—“repentance and good deeds”). In between are some 16,000 other entries, most no easier to decode. Imagine if English had 16,000 acronyms like CEO (“chief executive officer”), FYI (“for your information”), or ASAP (“as soon as possible”) that had to be learned in order to read it fluently!

Conversational Israeli Hebrew does not have so many acronyms as all that, but it has a lot more than does English. Some are rabbinic in origin, such as kanal (“ditto”, from k’ne’emar l’eyl, “as mentioned above”) or teyku (a draw or stalemate, from Tishbi y’tarets kushyot u-va’ayot, “the prophet Elijah will resolve all difficulties and conundrums,” said in rabbinic discourse of an undecided halakhic issue to be solved only in messianic times by the returning prophet). Most are modern. One finds them everywhere. In ordinary life: doḥ, a summary, report, or traffic ticket, from din v’ḥeshbon; luz, a schedule, from lu’aḥ z’manim; dash, regards, from d’rishat shalom; sofash, weekend, from sof shavu’a. In business and government: yor, chairman, from yoshev rosh; mankal, CEO, from m’nahel klali; yo’amash, attorney general, from yo’ets mishpati; bagats, the supreme court, from bet-din gavo’ah l’tsedek.) In the army: Tsahal, the Israeli army, from tsva haganah l’yisra’el; ramatkal, chief of staff, from rosh mateh k’lali; magad, a brigade commander, from m’faked g’dud; ḥapak, a war room, from ḥadar pikud. These are but a few of nearly endless examples.

I began writing this column this morning, the day of the Trump-brokered ceasefire, during which we were sent to our mamad by the Home Front Command a record number of four times before the shooting stopped. Now it’s time for a good, long shnats. That’s Hebrew for shnat tsohorayim, an afternoon snooze.