A quarantine was a restriction placed upon movement.
Having taken the Doctor's TARDIS on board their probe ship, the Morestran crew had it placed in quarantine. When Sarah Jane Smith exited the TARDIS, Controller Salamar had oxygen transferred into the quarantined area, recognising her dependency upon it. (TV: Planet of Evil)
In 51st century, the Tenth Doctor advised River Song to set up a quarantine beacon on the Library to ward away would-be visitors lest they come into contact with the Vashta Nerada. (TV: Silence in the Library)
In 5,000,000,023, when the Sisters of Plenitude's diseased test subjects broke out, Matron Casp ordered that the New New York Hospital be placed under maximum quarantine, resulting in incoming shuttles being diverted and all lifts being shut down. Frau Clovis attempted to override the quarantine and get a signal to New New York, though the Tenth Doctor warned that any forced entry would break the quarantine. Ultimately, the crisis was averted when the Doctor concocted a cocktail of medicines to cure the patients. (TV: New Earth)