Once upon a time, buying a new winter coat often meant getting caught between the proverbial "rock and a hard place."

The Rock: looking stylish. Sure, a leather bomber jacket oozes panache, but what happens when the mercury plummets below 40 degrees? Let's face it: A thin, waist-length garment simply doesn't do a great job at keeping out the cold.

The Hard Place: staying warm. True, a thick, bulky goose-down coat outfitted with a fur-lined hood lets you laugh at the cold. But for most business and social wear, the Nanook-of-the-North look just doesn't cut it.

Frustrating? You bet. As one New York fashion expert put it, "People who spend money on clothes are tired of looking good while freezing their rear ends off."

But take heart: Those were the bad old days. In 1992, buying a winter coat no longer means making the hard choice between style and function.

The trend this year is toward the best of both worlds -- a blend of the sensible and the aesthetic that not only looks good and keeps you toasty, but extends your wardrobe's range.

How was this minor miracle achieved? While traditional outerwear manufacturers aren't abandoning the classic overcoat, they are borrowing shapes, features and space-age materials found in active outdoor clothing.

And that's good news for anyone in the market for a new coat.

"What we're starting to see is a phenomenon called crossover dressing," says Brenda Drake, product development and design director for the specialty-fabric division of Milliken Mills in New York. "Manufacturers are taking features from skiing, shooting and backpacking outerwear and incorporating them into their everyday wardrobe."

The result, she says, is a winter coat that can fill several fashion niches.

The new trend actually got under way a few seasons ago when European and American designers such as Calvin Klein starting coming out with high fashion twists on the anorak -- a slimmer, upscale variation on the basic three-quarter-length, hooded pullover coat favored by mountain climbers.

Ms. Drake explains why the designer anorak is an innovative combination of warmth and style. "It's a very functional and aesthetic design that uses a high-tech, yet practical, fabric with a luxurious touch -- a microfiber." Microfibers are super-thin strands of nylon tightly woven into a durable, wind-resistant and extremely soft material.

And by adding space-age insulation such as Thinsulate -- a synthetic material that is said to provide almost twice the warmth of down -- manufacturers can create slimmer, warmer winter coats. And that, outerwear fashion experts say, increases a garment's versatility.

"There's a practicality in the new outerwear," says Helen Wagner, a spokeswoman for 3M, which developed Thinsulate in 1978. "It means a very sporty look can work for business dress, and business dress can work for social occasions."

Of course, multipurpose only goes so far: No one, for example, is suggesting that this new breed of winter coats should be worn at the North Pole. Yet many of this year's garments come with a wide array of snazzy features you'd expect to find on expedition wear.

"A lot of the details you'll find on fashion outerwear this year are what you associate with the real McCoy," says Don Vavala, an account manager at W. L. Gore and Associates in Elkton. The company manufactures Gore-Tex, a waterproof, breathable shell material frequently used in expedition clothing.

"Look for features such as double storm flaps on front zippers, inside waterproof pockets for keeping billfolds dry and 'pit zips' -- zippers mounted in the armpit area for ventilation."

While space-age materials are increasingly popular in fashion outerwear, that doesn't mean tried-but-true materials such as leather are passe.

For example, Timberland, famous for rugged leather footwear, has made a foray into the leather outerwear business -- but with a twist. The New Hampshire-based company's new line of classically styled field coats, bombers and wharf coats is made of leather that's fully waterproof and stain-resistant. Again, the operative word is versatility.

Colors, too, reflect the new down-to-earth practicality of this year's winter outerwear. In 1992, you'll find more subdued shades, especially when compared to the bright colors that predominated over the last few years.

"Neons are dead," Mr. Vavala declares, adding that most manufacturers are stressing rich, soft, earth-tones.

And prices? With consumers more value-conscious than ever, manufacturers are attempting to hold the line on costs, Mr. Vavala says. "Customers want a good garment that takes the place of several coats, or one that lasts many years. So we're not seeing dramatic price cuts or increases in the industry."

Retailers, confirming the trend toward functional, yet stylish, outerwear, report a strong demand for parkas and anoraks.

"We're leaning more toward three-quarter-length jackets that can dressy or casual, depending on the situation," says John Thompson, the manager of Hudson Trail Outfitters in Owings Mills Mall. "Customers like the parka-length jacket with the draw cord in the waist that you can cinch. It's more form-fitting."

While the slimmer silhouettes of this year's outerwear are a hit with consumers, so are relatively new innovations such as Synchilla: a soft, luxurious, synthetic fleece that's softer than cotton, can be warmer than goose down -- and doesn't itch like wool.

"All the major manufacturers of sweaters and jackets offer a polyester fleece that replaces wool and down," reports Matt Watkins, a salesman at Eastern Mountain Sport in Towson. "Unlike wool, you don't have to wear anything else under it. And, it looks nicer with a zipper down the front than a wool sweater."

But don't forget about layering, Mr. Watkins warns. "The only problem with fleece is that cold wind cuts right through it. That's why you need an outer, windproof shell."

One of the most successful shell materials on the market is Gore-Tex. Yet Gore, in an effort aimed at the fashion outerwear market, recently introduced a new shell material, "XCR Windstopper."

"XCR is different from Gore-Tex because it's not waterproof, but it is windproof and highly breathable," explains Lisa Wyre, a company spokeswoman. "XCR can be worn comfortably indoors part of a liner in wool sweaters and fleece pullovers, but is warm when worn outside -- even in cool, windy conditions."

In other words, says Ms. Wyre, it's versatile. And that seems to be the key word for buyers of outerwear in '92.

ADDING ON

This winter, it's not a question of style vs. function: These accessories not only look good, they do the job.

* It's the year of the balaclava: In soft, warm polyester fleece, the head-hugging knit cap with a full neck is warm and, unlike a wool cap, won't itch.

* Thick, soft polyester fleece headbands work wonderfully for active outdoors people who want to keep their ears warm without overheating.

* Look for glove "systems" that feature an outer glove made of leather and an inner liner of waterproof Gore-Tex.

* Here's a tip from skiers: Booties insulated with Thinsulate or other synthetic insulations are great for warming cold feet in front of a fire.

* "Light" hiking boots aren't just warm: Their informal look complements this winter's outerwear fashions.

* Warm and luxuriant polyester fleece is the fabric of choice in mittens, scarves and neck warmers.

* Leather and nylon backpacks are practical and complement this year's rugged style.

* A thick-soled chukka boot of moccasin construction can round out the new outdoors look.