The ornamental design for a watch, as shown and described.
FIG. 1 is a right front perspective view of a watch showing my new design;
FIG. 2 is a right side elevation view thereof;
FIG. 3 is the left side elevation view thereof;
FIG. 4 is a top plan view thereof;
FIG. 5 is a bottom plan view thereof;
FIG. 6 is a front elevation view thereof;
FIG. 7 is a rear elevation view thereof;
FIG. 8 is a right rear perspective view thereof; and,
FIG. 9 is a front elevation view of the dial portion of the watch shown separately for clarity of illusion.
The structural features depicted by broken lines have been shown for the purpose of illustrating portions of the watch that form no part of the claimed design.