The phrase "corkscrew curls" refers to hair that is tightly and spirally curled, similar to the shape of a corkscrew used to open wine bottles. Full definition
In a perfect world, after we wash our hair, the wet strands would coil up and separate into a fluffy pile of corkscrew curls. (elle.com)
Their coat is a combination of wavy and curly hair that forms corkscrew curls all over the body. (dogingtonpost.com)
With coats of corkscrew curls and ears that flop at the tips, the pumi (pronounced POOM» - ee) has a whimsical expression that belies its strong work ethic, fanciers say. (sandiegouniontribune.com)