FAIRFIELD is said to have been named for the beautiful open land that first attracted its founder, Roger Ludlow, back in 1639. Today, the fields have yielded to development and the latest proposal is to build seven houses on the 15.2-acre estate of Mather Whitehead, a gridiron star from the Yale University class of '36, and his wife, Elizabeth Uihlein. The prospect has neighbors, historic and architectural preservationists ready to wage a battle of protest. The latest skirmish site: a hearing before the Town Plan and Zoning Commission on Tuesday to review revised plans for the site.

The Whitehead estate, Burrwood, is a two-story gable-roofed Greek Revival house built in 1819 at 1555 Burr Street, in what is now the Greenfield Hill section of town. Opponents of its development point to the Meadows at Riverfield, a 14-lot subdivision on the site of the Charlotte Danczak estate on four acres two miles south, to underscore their objections.

Since early spring, 11 of the 14 houses (on quarter-acre lots) have been bought, commanding an average of $450,000.

''It's a new phenomenon,'' says the Fairfield First Selectman Paul Audley, describing the placement of large houses on small lots.

''New construction is very much in demand,'' says Marilyn Longden, an agent at William Raveis Real Estate, one of the brokers selling the property. ''Prospective buyers are usually high-powered couples who don't have time to take care of a house. Many are mobile families and know the resale value will be good.''

The site is especially attractive, she said, because the new houses are in an established neighborhood, close to an elementary school and near Interstate 95 as well as to MetroNorth Commuter Railroad and shopping.

The town had tried to fight the development plan by buying the property for athletic fields for the school. But the town, which is restricted by town charter to bid only fair market value, was outbid by the developer.

At that point, a land acquisition committee was formed, charged with setting up criteria for the purchase of open-space property as it becomes available. The committee's first draft report has just been prepared.

''It's too little, too late,'' says Ellen Curtis, a member of the Fairfield Garden Club who was one of the key opponents to the Meadows subdivision. ''All these years there should have been something in place,'' she said.

Is it too late for Burrwood?

Mark Richards and his wife, Doreen Gebbia, who live nearby, don't think so and they have hired a lawyer. Mr. Richards said they would settle for a compromise: two houses instead of seven in return for saving the old house and the property's other significant characteristics.

Burrwood was included in a survey of Fairfield historic buildings by the Connecticut Historic Commission, which recently placed the house on the state's register of historic places, and the Fairfield Historic Society for listing on the National Register of Historic Places.

Burrwood, done in Greek Revival style, was built by Lewis Burr, a farmer and member of one of Fairfield's original families. The house remained in the Burr family until 1945 when the Whiteheads bought it. In 1947 the landscape architects Stuart Ortloff and Henry Raymore, of Huntington, N.Y., worked on the grounds; Cameron Clark designed the interiors.

''The gardens are outstanding,'' said Donna Caldwell, a landscape designer and Greenfield Hill resident. ''The property is rich in rare specimens,'' she said, including fernleaf beech and umbrella trees, mature rhododendrons and a 50-foot redwood, a Meta Sequoia.

The developer, David Bienshaski of Monroe, had originally planned to build six houses and keep the Whitehead house. But when the town rejected his plan for line-of-sight reasons, he changed the location of the proposed road, which would require that the house be demolished. The revised plan drew the opposition.

William Fitzpatrick, the lawyer representing the developer, said he did not hear a word of support for the first plan, even thought it included preserving the house.

''When you look at the site, where we originally proposed the road is the only place we could put the road and save the house,'' he said. ''If I can find a compromise that serves my clients and those who want to save the house, I would be interested. Maybe someone would transfer the house to another site.''

Marcia Miner lives in the Benson House, which has been in her family since 1809. ''I don't object to the subdivision,'' she said. ''I recognize that people have a right to subdivide. I'm concerned about saving an historic house. There's a real feeling the developer is being greedy.''

Taxes are a problem though. ''It is getting harder and harder to maintain acreage as taxes go up,'' says George Rockwell, president of the Greenfield Hill Village Improvements Society, a 101-year-old organization with more than 700 member households among the 2,200 in Greenfield Hill. ''Large tracts of land are becoming fewer and fewer,'' he said.

Martha Stewart has bought two adjacent parcels of land, one with a house, on Bronson Road, totaling 35 acres. The Dupont family owns more than 50 acres on Hulls Farm Road. ''People come to this area for peace and quiet. They don't relish people looking around at them,'' said Mr. Rockwell, a 40-year resident of Greenfield Hill, where Leonard Bernstein and Richard Rodgers once lived.

The development plan causes some to ask whether it is better to develop land and expand the tax base or to acquire the land for open space to maintain a quality of life.

Robert Saxl, a Westport lawyer and longtime Fairfield resident who heads the land acquisition committee, said, ''Development per se doesn't necessarily put money into the town coffers. An analysis of the town's Sarah Woods property, an 84-home subdivision built on 116 acres in 1984, shows that it costs the town just over million dollars to educate its 90 children and provide other municipal services. With the town collecting tax revenues of $790,000 from the homeowners, it is losing $220,000 a year.'' The town could have floated bonds to buy the property, he said, owning the open space after about 15 years.

The land acquisition committee is recommending the modification of a town ordinance, allowing the town to be more competitive when properties go on the market. Specifically, it is recommending that the town achieve a ratio of 70 acres of open space to 1,000 people as suggested by the Connecticut Inter-Regional Planning Program. (It is currently 53 acres per 1,000.)

The committee also recommends that land be targeted for passive or active use, location, size, conservation and esthetic value, recreation value, and development potential for town buildings, infrastructure or other town sponsored development.

Financing could come from various sources, from private donations to charging taxpayers a half-mill rate or by taking 10 percent of the budget surplus each fiscal year.

Committee members say competitive pressure from developers is inevitable and indeed understandable, but that there is an obligation to preserve the basic character of the town.

The First Selectman would like to see a compromise worked out with the Whitehead property, in which the house would not have to be demolished and the traffic pattern would make sense. Among other reasons for acquiring property, he added, were that the town did not have enough space for athletic programs, for schools or for recreational needs.