The ornamental design for a waterbottle, as shown and described.
FIG. 1 is a left-side perspective view of the water bottle showing our new design;
FIG. 2 is a left side view of the water bottle shown in FIG. 1;
FIG. 3 is a right side view of the water bottle shown in FIG. 1;
FIG. 4 is a rear view of the water bottle shown in FIG. 1;
FIG. 5 is a front view of the water bottle shown in FIG. 1;
FIG. 6 is a top view of the water bottle shown in FIG. 1; and,
FIG. 7 is a bottom view of the water bottle shown in FIG. 1.
The broken line showing of portions of the water bottle is included for the purpose of illustrating environmental structure and forms no part of the claimed design.