Tea bag

A tea bag was a porous bag that contained tea leaves.

Tea leaves were sometimes encased in porous bags, making it easier to dispose the leaves after steeping.

Following his escape from a helicopter, Alexander Christian raided the Doctor's House for money and supplies. One of the things he took were tea bags. (PROSE: The Dying Days)

The Eleventh Doctor used a large number of tea bags to make a strong tea that he used to save Craig Owens life. (TV: The Lodger)