Although it has always meant an isolationist monastic, the term »anchorite« has had two rather different meanings. Originally, it simply denoted a hermit: what Benedict describes in his Rule as the second order of monks. During the High Middle Ages, however, the sense of the word shifted to a practice of ascetics having themselves permanently locked up in a small cell within an abbey, or even being bricked in alive, there to meditate on God and the mysteries of religion, which is remarkably extreme even compared with eremitic life in the waste. This cell would be constructed as part of a church or abbey chapel, and have one or more apertures through which the anchorite could hear Mass, receive the Eucharist and also handle more mundane practicalities like food and water, removing bodily waste, and speaking to petitioners for their supposed heavenly wisdom. (Technically speaking, I believe, it is still permitted within the Catholic Church to become an anchorite of this type, although whether any living person currently is seems to me to be very doubtful.)
In the early Church practice of the first type, anchorites (that is, hermits) were almost all men, as the term Desert Fathers implies; in the post-schism Church, however, when practice had shifted to the second type, there were many more women than men choosing the life. Bizarre as the practice seems now, it does seem to me that there will always be among mankind a certain proportion of neurotics predisposed toward an obsession with extreme piety, and that although bricking them into the wall seems a touch excessive, our ancestors were probably wise to effectively remove them from society in a way that allowed them to placate their neurosis.