Twelve years in the making and tipping the Toledos at a healthy 51/4 pounds, the Dictionary of Occupational Titles includes in its 1,371 pages descriptions of just about every profession an able-bodies American might have, except the world's oldest.

"Oh, no," said a spokesman for the Department of Labor's Employment and Training Administration, compilers of the massive tome, "We don't normally get into that kind of thing."

What the dictionary does get into is 20,000 job descriptions, everything from abalone diver ("gathers or harvests marine life") to zyglo inspector ("applies iron oxide and zyglo solutions to ferrous metal parts").

Each job has its own "unique 9-digit code number" and is grouped systematically with other, similar jobs. For instance tooth inspector ("examines, sorts and packages artificial teeth"), which is not to be confused with a tooth clerk ("selects false teeth used to make dental plates"), is found on the same page as artificial glass-eye maker ("fabricates artificial glass eyes for humans").

Down at the Employment and Training Administration, folks want it emphasized that this is a serious book with a serious purpose: describing actual, existing jobs so that qualified people, with the help of guidance counselors, can be found to fill them. That's why the book has gone through four editors since first coming out in 1939. How else, for instance, could one fill the position of poet without consulting the following definition:

"Writes narrative, dramatic or lyric poetry for magazines, books and other publications: Choose subject matter and suitable form to express personal feeling and individual experience, or to narrate story or event. May write doggerel or other type verse."

But really seriously, folks, it is impossible to wander through this particular dictionary, which is available for $12 at the Government Printing Office, without finding job titles and/or descriptions that are at once staggering and humbling in theie deadpan inclusiveness. Not only do we have everything in this great land of ours, we've even got people to detail painstakingly exactly how much of everything we have.

In the entertainment area, for instance, there are weight-guessers ("serutinize patron's physique and make oral estimate of weight"), character impersonators ("impersonates traditional holiday or storybook characters, such as Santa Claus, Snow White and the Three Little Pigs") and even (gasp!) showgirls ("parade across stage to display costumes and provide background for chorus line to entertain audience").

If sports appeal, one may ponder the life of a bowling ball finisher ("tends buffings machine that removes scrathes and polishes surface of bowling balls") or a golf ball cover treater ("tends machines that tumble balls in solutions to vulcanize, ctch and cure covers preparatory to painting") or if one feels maudlin, pity the poor tennis ball cover cementer, who "wears gas mask when fumes become too objectionable."

If food makes you thoughtful, consider life as a pretzel twister ("twists round strips of dough to form pretzels"), a blintz roller ("fills precut sheets of egg dough with cheese, folds ends over filling and rolls lengthwise"), an egg breaker ("strikes egg against bar, allows contents to fall into bowl and throws empty shells into a receptable"), or even a potato chip sorter, "observes potato chips on conveyor and removes chips that are burned, discolored or broken."

And speaking of burned, discolored and broken, the dictionary even reminds us that life is not all fun and games, and its precise, hard-nosed definitions of less than elegant tasks like embalmer, artificial inseminator and offal separator are not such as can be safely quoted in a family newspaper.

Among the 20,000 jobs, most of which are useful, important positions, titles pop up that somehow seem in a world of their own, special tasks that you wish you could have if only for a day because they would look so good on the jacket of your next novel. Personal favorites include:

Feather removator - "cleans feathers for reuse in pillows."

Drifter - "tends drifting machine that removes scale from inner surfaces of pine."

Maturity checker - "tends machine that mashes peas and registers force required to crush them to ascertain hardness."

Leacher - "tends leach tanks that recover soda ash from black ash."

Whizzer - "tends machine that spans felt hat bodies to remove excess water."

Dog bather - "bathes dogs in preparation for grooming."

Bomb leader - "loads, assembles and packs aerial bombs."

Rubber - "massages and bathes customers in thermal bathouse. Kneads, slaps, strokes and rubs flesh with stiff-bristled brush or brush made of leaves and twigs to increase circulation, relax muscles and relieve fatigue."

Mail censor - "reads incoming and outgoing correspondence . . . of prisoners with adjustment problems or suspected of forbidden activities, such as planning escapes or attempting to contact confederates outside prison."

Lamp inspector - "inspects lumps of tobacco for defects in wrapper leaf."

Mother repairer - "repairs metal phonograph record mother (matrix).

Seqain slinger - "tends machine that automatically interlaces thread around strings of sequins in such a manner as to separate, space and hold fast sequins."

Continuous pillowcase cutter - "tends machine that cuts rolls of tubular cloth into pillowcase length."

Lingo cleaner - "cleans metal lingos (weighted heddles) used in Jacqaard loom harness."