The mannish mode

All that talk about the gender gap does not apply to the latest clothes. Fashion is doing its best to bring the sexes together, so that as far as external appearance is concerned, they will meet on a more or less equitable basis.

The leading trend for women - as just about everyone must have heard by now - is the mannish mode, otherwise known as the androgynous look. A homogenization of menswear with women's styles, it is a practical way to dress and is neither severe nor hard edged. On the right sort of woman it has a rather beguiling effect. Whether or not it can work its magic in narrowing the male-female divide to any substantial degree is one of those arguable questions. It might have the reverse result. Women who appropriate clothes belonging to their gentlemen friends often come off looking as if they need a Big Strong Man's protection.

And indeed, not content with simply borrowing from masculine haberdashery, designers have enlarged on the idea so that the jackets, topcoats, shirts, and sweaters to be found in the stores now seem to be one or two sizes bigger than their hangtags indicate.

Pants, which are an important element in the fall lineup, are generally baggier than they have been, although they do fit around the waist. Belt loops and cuffs are popular details.

Skirts are sometimes straight, but much more often wide and flaring; in either case they are so much longer for daytime that they can on occasion hit the shoe-tops. (Even dresses that were knee-length last year have gained a few inches of hemline.)

Coats, the most ample of the new pieces, tend to have exceedingly broad shoulders, the better to balance the breadth and length of most styles.

While the grand scale of these garments, if taken all together, could swamp the average-sized person, a judicious choice of a few pieces will rev up the separates that are holdovers from previous years. New buys to consider are (1) a big coat, (2) an elongated oversized jacket, (3) a couple of first-rate pure silk white shirts, (4) pleat-top gabardine or flannel trousers, and (5) a below-calf circle skirt. A sweater vest or jacket, one of the new tailored dresses in a shirt or coat style, a fedora or beret, and some down-to-earth pumps would fill out such a shopping list. By concentrating on dark and neutral tones (which isn't hard to do this season) and adding accents of neon-bright colors, the canny shopper can come away from a foray into the stores equipped for any eventuality: workday and travel.

The fashions that take their cues from menswear are mainly proposed by such influential names as Calvin Klein, Ralph Lauren, Perry Ellis, and Anne Klein & Co., and they are aimed primarily at the Yuppie population. Young urban professionals, the two-income types particularly, will know how to adapt and modify the oversized mannish look for their career needs. It is this customer who will go to dinner parties in the Lauren men's forest green velvet dressing gown, with beaded crest and tasseled silk cord sash, over a silk shirt and tuxedo pants - or failing that, will buy a man's paisley robe and wear it in a similar manner.

This is not to say there are not plenty of choices in the fall fashion scheme. Quite the contrary. No one hemline, color, or style is being prescribed for everyone to follow. Little skirts worn with tights of matching color are just as acceptable as suit skirts a couple of inches below the knee, or as the superlongs. Beltlines also shift around according to preference, or the mood of the moment, going from the normal waist to hip-band, the latter being a stylish placement for satin or lame evening sashes.

There's less emphasis on black (and more on white for individual components as well as entire outfits) in favor of russet, bark brown, deep green, loden, and navy. But hot cerise, flaming red, vivid blue, and yellow - shown by Oscar de la Renta and Bill Blass in jackets and coats - are definitely in the fashion mainstream, too.

Sweaters and knitted clothes are key parts of the fall picture, in stitches plain and fancy. Adrienne Vittadini's knit coats and jackets of tartan patchwork , Kasper's cabled jumper dress worn over a silk shirt and tie, and Calvin Klein's jersey tailored dresses are among the standouts.

Cashmere tops an array of yarns fashioned into vests, pullovers, jackets, dresses, and wraps. The twin set rates high, especially the cashmere combination of ultralong cardigan over short matching sweater, and the luxurious twin set has been given new life as an evening style. The Blass examples, shown with satin or lace bouffant skirts, set the standard. They reflect the feeling of casual ease that pervades all of this season's dressing, from dawn to dark.