HRU has been grilling PDA about that KVC report on overruns.

That statement makes about the same amount of sense to you and me as the following fragment of conversation does to a Washington newcomer: "OMB has been grilling DOD about that GAO report on overruns."

How soon we forget that the rest of the country's knowledge of government-body initials includes the FBI, CIA, IRS and little else.

As a matter of fact, we don't have to work for or with the government to be swept up in a specialized body of abbreviations and argot.

I know several hospital volunteers who had no previous medical experience except as patients, and now they talk of the ICU, EEGs, bluebacks, charge nurses, going to pedes, and a rescue arriving with a CPR. Of course these folks are still not in the same league as doctors, who can talk as obscurely as they scribble prescriptions.

Computer land is another territory with its own special babble. My son-in-law the software engineer is very proficient in it, from bits and bytes to CPUs, MUXs, IBGs, IPLs, re-booting and debugging. But he moved recently to a company providing telecommunications by satellite, and now he has another foreign language to learn--aerospace.

The other night he showed me a sentence from a report he was studying: ''NLT TIME FOR POCC TO PROVIDE MCC WITH CHANGES TO OUT-OF-PLANE PKM BURN COMPONENT AND NUMBER OF SECONDS PRIOR TO EQUATORIAL CROSSING FOR PKM IGNITION.''

He had a better grasp of its meaning than I did, but not by much. And that sentence was not any denser with unexplained abbreviations than many other parts of the document.

At The Washington Post, abbreviations are not so rampant. But we do have a "mail room" that has nothing to do with mail, newsroom "budgets" that have nothing to do with money, "signatures" that are neither names nor signed, and "printers" who don't go near a press. And with "editors" who are outranked by "assistant managing editors," our hierarchy is not instanteously apparent, either.

None of these observations is really a complaint. It's hardly surprising that idiosyncratic use of language evolves within different professions. And I'm certainly sympathetic to the amount of breath, time and paper that abbreviations save--particularly in the spheres of government, medicine and technology.

But pity the poor newcomers to our various worlds. Most of us are good about answering their questions and trying to be helpful. Yet every so often, when we're not available for questioning, we drop messages on them that are far more cryptic than we realize.