A time or temporal barrier was a force field-like defence. Everything within the barrier could be projected a least a second into the future, preventing any energy or anything physical from penetrating to the other side. (TV: The Face of Evil)
The Library on Kar-Charrat was protected by a temporal barrier created by a time field generator. (AUDIO: The Genocide Machine) Archetryx was protected by a temporal barrier that kept the planet existing one minute into the future. (AUDIO: The Apocalypse Element) Robert Knox placed Edinburgh in a time barrier, which allowed him to reset and play out events repeatedly. The Doctor's TARDIS was able to pass through the barrier. (AUDIO: Medicinal Purposes)