protuberate

pullistaa

pullistua puhekieltä To bulge outward, producing a rounded protuberance.
1844, Henry O'Shaughnessy, "Modern Shoemaking", The Mechanics Magazine, Museum, Register, Journal and Gazette'', Vol. 40, No. 1067, p. 42:

With respect to measurement, it would be advisable to take the circumference of the foot by placing the beginning of an inch tape measure a little beyond the great toenail, as the second toe is naturally the longest, passing the measure round the protuberating part of the heel, and bringing it up to the point of the beginning of the measure at the toe.