The ornamental design for an inflatabledinosaurcostume, as shown and described.
FIG. 1 is a perspective view of an inflatable dinosaur costume showing my new design;
FIG. 2 is another perspective view thereof;
FIG. 3 is a front elevational view thereof;
FIG. 4 is a rear elevational view thereof;
FIG. 5 is a left side elevational view thereof;
FIG. 6 is a right side elevational view thereof;
FIG. 7 is a top plan view thereof; and
FIG. 8 is a bottom plan view thereof;
FIG. 9 is an enlarged view of portion 9 shown in FIG. 1;
FIG. 10 is an enlarged view of portion 10 shown in FIG. 1; and,
FIG. 11 is an enlarged view of portion 11 shown in FIG. 7.
The broken lines in the drawings depict portions of the inflatable dinosaur costume that form no part of the claimed design. The dot-dash broken lines represent boundaries of the enlarged portions and form no part of the claimed design.