Prime Minister Tony Abbott's understanding of the technical aspects of the work carried out by Australia's spy organisations has been questioned in the Senate.
Fresh documents leaked by fugitive US whistleblower Edward Snowden revealed the Defence Signals Directorate (DSD) discussed sharing "medical, legal or religious information" with foreign intelligence partners.
Mr Abbott has defended Australia's intelligence agencies, saying their gathering of telephone and email metadata is within the law.
But Greens senator Scott Ludlam says Mr Abbott's description of metadata as "billing info" falls short, as such data reveals a person's web history, social networks and entire phone records.
"Can the attorney please give an undertaking to remind the prime minister what this term actually means," Senator Ludlam asked Attorney-General George Brandis in the chamber.
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Senator Brandis defended the prime minister, saying the term meant different things to different people and several definitions had been offered in a recent parliamentary inquiry.
"I myself ... thought that the prime minister's description of metadata as essentially billing details was a perfectly accurate shorthand description of what is a contestable concept," he said.
He said the federal government was "confident" Australia's intelligence agencies conducted their work in the interest of all Australians, adding they operated under a regime of strict parliamentary oversight.
