The English language has an abundance of words that all imply a light brownish-gray color. Different designers commonly use different words for the same color, or the same word for very different colors. For purposes of stylistic discussion they all perform about the same -- you won't find any set of circumstances where a "tan" tailored suit would be appropriate but “khaki" wouldn't be. In their most common usage the different styles of light coat break down as follows:
- Tan refers to light, predominantly brown shades.
- Dun refers to a darker brown than tan, sometimes with a greenish tint.
- Khaki is the most dominantly yellow shade of the related colors, with little brown or gray.
- Taupe is a darker color with gray tones as well as brown.
These are, however, only general guidelines, and every store or designer will have a slightly different take on each color. It's not impossible to see other terms as well -- just remember that, from a stylistic standpoint, they all follow the same rules. Which one to purchase will be a matter of taste, complexion, and budget?
Formality of the Tan Suit
Light colors similar to tan are not as formal as their darker counterparts. Brown suits in general have been a historically informal choice, and have only recently been embraced as business-wear by men looking to break-up the monotony of dark color in their wardrobe. The lighter versions are still considered purely social wear or seasonal wear by those who adhere to strict dress rules.
Lighter color suits are also associated with spring and summer, their lighter shades signifying the lightness of the season. Trying to wear a light colored suit in New York City during December not only invites odd looks but opens a man up to the impracticality of keeping it clean from muddy slush. Light colored suits are best for dry & warm weather.
As a result, tan suits are usually considered business-casual wear. They may well be appropriate attire for daily work at more relaxed offices, but will not serve at formal meetings or serious occasions. These lighter suits shine best when worn for social and relaxed occasions -- as poisonous as the term "leisure suit" has become, with its brightly-colored polyester associations, that's exactly what most light brown/yellow/gray suits are made for.
They're a relaxed choice for men who prefer to appear well-dressed even during their personal time. Patterning may be used to make the bespoke suit still more casual. Both stripes and checks are common in light brown suits, including subdued plaids of varying earth-tones.