(FORTUNE Magazine) – DISINFLATION has barely settled into the everyday economic lexicon, but the word is already on its way to obsolescence. After slowing for five years, the rate of inflation is due to turn up again. The acceleration will be gentle but persistent, spurred in the short run by rising import prices and, if it passes, the Senate Finance Committee's tax reform proposal. Foreign producers have not been able to absorb all the costs of the falling dollar. During the first quarter, prices for imported goods other than fuel were up more than 6% from the year before; in 1985 they rose less than 1%. FORTUNE expects that the dollar has about finished its downhill run. But excluding fuel, costlier imports will add as much as a full percentage point to inflation during the next year. The effects of import prices on the GNP deflator are indirect since they are not included in gross national product calculations. But capital equipment or materials and parts account for nearly half of the $350-billion annual import bill, and the higher costs of these will start to show up in prices of U.S. companies. Wholesalers and retailers of imports, who appear to have been enjoying fat profit margins, may not boost prices in step with their rising costs. Like foreign manufacturers, though, they are running out of room to swallow price increases. Consumers are already paying roughly 10% more on average for foreign cars, and Joel Popkin, a price and inflation consultant, estimates that they will soon pay 7% to 8% more for imported VCRs, TVs, and many other finished products. The swift part of the energy joy ride is over. The spot market price of crude oil has stabilized in recent weeks at between $15 and $16 a barrel, up about $4 from lows reached in early April. The latest Department of Energy forecast of $18 a barrel by early next year seems a reasonable guess. With the turnaround in crude prices, prices for petroleum products will at least stop falling, and some could inch back up. The change will appear soon in consumer prices. Excluding energy, the consumer price index increased at a 4.3% annual rate during the past six months. That was more than a percentage point faster than in the previous half year and over 2 1/2 times the 1.6% rise for the total CPI. So-called core inflation, leaving out both food and energy, has been escalating even faster, at 4.7% a year. Once the prices of gasoline and fuel oil stop declining, as they are likely to this summer, overall consumer inflation will move toward this core rate. The best news about inflation is that labor costs show no signs of surging. After a dismal performance during 1985, productivity will improve a bit (see next story). Wages and fringe benefits will accelerate slightly later this year. But the increase will be less than 4% through next spring (see chart). The heavy 1986 bargaining calendar includes the communications workers, some 675,000 strong; they are used to getting large increases and will probably win another this year. Though the union no longer has the giant AT&T to deal with, the Bell operating companies have proved quite profitable. Still, a large number of workers covered by expiring contracts are in the depressed metals industries. So wages in the union sector will not lead the way. Most of the action will be where most of the jobs are: in the growing non- union portions of the economy. What matters for inflation is not that non- union workers get less than union workers but that their wages and benefits have been rising appreciably faster, at a rate of better than 4% a year. Increases next year could be larger, though tax reform's lower rates would soften some of the clamor for higher pay. Cutting both ways, tax reform could also make it hard for many businesses to maintain profit margins in the short run. FORTUNE estimates that after-tax margins will be down for the first half because oil company losses are overshadowing other companies' savings from lower energy costs. With the economy growing slowly and import competition still fierce, business will not raise prices enough to improve margins during the coming year. For most businesses, indeed, raising prices is increasingly a last resort: managers are under pressure to hold down costs instead. But if the investment tax credit disappears, margins would be reduced even further. Though many companies would make up some of the loss or come out ahead later when lower corporate tax rates kicked in, the early hit on earnings could outweigh caution about losing market share for those that cannot make themselves more efficient. The GNP deflator, the broadest measure of inflation, will increase 4% between this spring and next, compared with a 2.8% rise during the last year. Since rising prices have fed upon themselves in the past, even the slight turn from disinflation is a warning signal. (The warnings from monetarist economists are more dire: see Other Voices.) But this recovery has already broken the mold ^ for longevity. It could also avoid the curse of creeping inflation.