The ornamental design for a showerhead for a coffeemaker, as shown and described.
FIG. 1 is a top right perspective view of a showerhead for a coffee maker showing our new design;
FIG. 2 is a top left perspective view thereof;
FIG. 3 is a top view thereof;
FIG. 4 is a bottom right perspective view thereof;
FIG. 5 is a bottom left perspective view thereof;
FIG. 6 is a bottom view thereof;
FIG. 7 is a right side view thereof;
FIG. 8 is a left side view thereof;
FIG. 9 is a rear view thereof;
FIG. 10 is a front view thereof; and,
FIG. 11 is a second bottom right perspective view thereof.
The even-length and uneven-length broken lines immediately adjacent to the shaded areas represent the bounds of the claimed design and form no part thereof. The even-length broken lines depicting the remainder of the showerhead show features that form no part of the claimed design.