Washington's National Aquarium, not to be confused with Baltimore's new and similarly named attraction, has been given a short-term lease on life while two Cabinet wives spearhead an effort to keep it open permanently.

The aquarium, located in the basement of the Commerce Department building although operated by the Interior Department, was one of the first targets of Reagan administration budget cuts.

Interior's 1982 appropriations bill, signed into law Dec. 23 by the president, omitted $289,000 that would have kept the aquarium operating until next Sept. 30. However, aquarium director Craig Phillips said the head of Interior's Fish and Wildlife Service, Robert Jantzen, agreed to maintain the aquarium until the end of February to provide time for the newly formed National Aquarium Society to arrange a permanent rescue.

The request for a reprieve was made by Midge Baldrige, wife of Commerce Secretary Malcolm Baldrige, who has been joined in the rescue effort by Sue Block, wife of the secretary of Agriculture.

Under consideration is a plan to turn the aquarium over to a nonprofit corporation, which would charge a nominal admission fee to pay for operations. The ultimate decision would be made by Interior Secretary James Watt.

About a half-million schoolchildren and tourists visit the aquarium annually to view 1,000 species of fish. Although located at its present Federal Triangle site only since the late 1920s, the aquarium began at another location in 1873 and is the third oldest such facility in the nation.