Bilis Manger claimed that he could walk through eras as Gwen Cooper would walk into another room. (TV: End of Days)
The Rassilon Era and Humanian Eras were examples of eras in the wider universe. (TV: Doctor Who, AUDIO: Neverland)
The Silurian era was an era on the planet Earth. (TV: Doctor Who and the Silurians)
The Ninth Doctor cited the Fourth Great and Bountiful Human Empire as an era with "fine food" and "good manners". (TV: The Long Game)