Толковый словарь английского языка - extension

noun Etymology: Middle English, from Late Latin ~-, extensio, from Latin extendere Date: 15th century 1. the action of extending ; state of being extended, an enlargement in scope or operation , 2. the total range over which something extends ; compass, denotation 4, 3. the stretching of a fractured or dislocated limb so as to restore it to its natural position, an unbending movement around a joint in a limb (as the knee or elbow) that increases the angle between the bones of the limb at the joint, a property whereby something occupies space, an increase in length of time, a program that geographically extends the educational resources of an institution by special arrangements (as correspondence courses) to persons otherwise unable to take advantage of such resources, 7. a part constituting an addition, a section or line segment forming an additional length, an extra telephone connected to the principal line, a length of natural or synthetic hair that is worn attached to one's natural hair, a mathematical set (as a field or group) that includes a given and similar set as a subset