The ornamental design for a medicaldevice, as shown and described.
FIG. 1 is a front view of a medical device in accordance with the new design;
FIG. 2 is a bottom perspective view of the medical device;
FIG. 3 is a top perspective view of the medical device;
FIG. 4 is a back view of the medical device;
FIG. 5 is a right-side perspective view of the medical device; and,
FIG. 6 is a left-side perspective view of the medical device.
The broken lines in the drawing views are included for the purpose of illustrating portions of the medical device that form no part of the claimed design.