TRIM, THE CEILING on Prince George's County tax revenues, was meant to stop the growth of government - but it may curb development, too. At least that's what county executive Lawrence J. Hogan has concluded. Last week he made the point emphatically by proposing to deny or defer nearly all pending requests for sewer hookups during the next decade. His plan, now before the county council, would not stop projects already approved, but would postpone more than 8,000 single-family homes, 3,071 town-house units and 996 apartment units planned by developers.

Such a slowdown may sound harsh, but the new math dictated by TRIM works out that way. Development is seldom free; more homes and people mean more demands for public services. Normally, residential growth at least partly pays for itself through new property-tax revenues. But since the voters put a ceiling on total tax collections, the usual revenue gains will have to be foregone. The county is having enough trouble stretching its tightly limited budget to cover inflation. Rapid population growth could impose intolerable strains.

Mr. Hogan is especially interested in slowing down the most costly kind of development, that located in semi-rural areas where police and fire protection, schools, transportation and other public services are still sparse. He would prefer to concentrate private investment around Metro stops and in close-in communities where basic facilities are already in place. Even without TRIM, Prince George's would have ample reason to encourage more compact, energy-efficient growth and avoid more low-density sprawl. In short, TRIM may make the sound course imperative.