THE BAKER ADMINISTRATION is adopting a definition of the word fare that would allow the MBTA to increase the prices of bus and subway passes at any time and by any amount.

A state law passed in 2013 limits MBTA fare increases to no more than 10 percent every two years. The Baker administration this week said it is taking the position that bus and rail passes are not fares and are therefore exempt from the law.

The issue arose on Monday when the T’s Fiscal Management and Control Board voted unanimously to seek public comment on two options for fare increases that would take effect July 1. One option would increase base fares 5 percent and the other 10 percent, while both approaches would boost the cost of many popular passes by greater amounts.

The popular LinkPass, which offers unlimited bus and subway travel, would go up 12.5 percent under one of the proposals. The local bus pass would go up 16 percent under one option and 19.5 percent under the other.

Transportation Secretary Stephanie Pollack said both of the fare options being mulled by the T’s oversight board comply with the 2013 law because base fares and overall system-wide fares would not increase more than 10 percent. Under both options, Charlie Card fares would increase less than 10 percent. The system-wide fare increase under the first option is 6.71 percent and 9.77 percent under the second.

“A pass is not a fare,” Pollack told reporters. “A pass is actually a discount from a fare, and that is the legal interpretation. So that is why we are proposing two different changes in fares. No fare goes up by more than 10 percent. System-wide fares don’t go up by more than 10 percent. But we’re giving less of a discount to pass holders in both scenarios.”

Jacquelyn Goddard, a spokeswoman for the Department of Transportation, said in an email that the definition of fares cited by Pollack “is based upon the common understanding and usage of those terms and is contained in the MBTA’s fare policy.”

The transit agency’s fare policy doesn’t specifically define a fare, but it does draw a distinction between fare media (Charlie Card, Charlie ticket, and cash) and unlimited ride passes.

Asked whether the T’s definition for fare would allow increases in T pass prices at any time and by any amount, Goddard said: “The MBTA’s position is that our passes offer a discount from the fare, and that the MBTA has discretion as to whether to offer such discounts, and, if so, in what amounts.”

Rafael Mares, vice president of the Conservation Law Foundation, said he was surprised at the administration’s definition of a fare. He said he suspected most people would think what they pay to ride the T would qualify as a fare, whether they purchased a Charlie ticket at the station or a month-long pass through their employer.

“They’re trying to change the meaning of words in order to change the cost of public transportation every year,” he said.

Rep. William Straus, the House chairman of the Legislature’s Transportation Committee, said he didn’t see a difference between paying with a pass and paying with a Charlie ticket. “I didn’t understand the distinction she appeared to be making,” the Mattapoisett Democrat said. “I’d be surprised if there’s a legislator voting on these types of issues who thinks there’s any kind of difference there.”

Sen. Thomas McGee, the Senate chairman of the committee, had a similar take on Pollack’s remarks. The Lynn Democrat said the meaning of the word fare is probably a gray area in the law that the Legislature may need to clarify, but he said most people wouldn’t see a distinction between an MBTA pass and a fare.

“It seems to me they’re all fares,” he said. “It’s what you pay to get on. I say absolutely it’s a fare.”