boattails

Example:The bulkhead was designed with simple straight lines, avoiding any bulges or boattails.

Definition:A portion of an object that juts out or projects outward, in direct opposition to a boattail shape which tapers.

Example:The car's bonnet had a bump in the middle rather than a boattail tapered shape.

Definition:A slight, rounded protrusion that is also in contrast to a smooth, tapered boattail shape.