Visiting scholar

In academia, a visiting scholar, visiting researcher, visiting fellow, visiting lecturer or visiting professor is a scholar from an institution who visits a host university to teach, lecture, or perform research on a topic the visitor is valued for. In many cases the position is not salaried because visitor is salaried by their home institution (or partially salaried, as in some cases of sabbatical leave from US universities). Some visiting positions are salaried. 
Typically, a position as visiting scholar is for a couple of months or even a year, though it can be extended. It is not unusual that host institutions provide accommodation for the visiting scholar. Typically, a visiting scholar is invited by the host institution. Being invited as a visiting scholar is often regarded as recognizing the scholar's prominence in the field. Attracting prominent visiting scholars often allows the permanent faculty and graduate students to cooperate with prominent academics from other institutions, especially foreign ones.
In the UK, a visiting scholar or visiting academic usually has to pay a so-called "bench fee" to the university, which will give access to shared office space and other university facilities and resources (such as the library). Bench fees vary across UK universities.
The purpose of a visiting scholars programs is generally to bring to the university or educational institution in question an exceptional senior scholar who can contribute to the community's intellectual and research endeavors and international projection. Hence, in addition to conducting their own research, visitors are often expected to participate in productive institutional activities, such as: