What is the meaning of Winkle?

A periwinkle or its shell, of family Littorinidae.

Any one of various marine spiral gastropods, especially, in the United States, either of two species Busycotypus canaliculatus and Busycon carica.

The penis, especially that of a child rather than that of an adult.

Synonym of winkle out (to acquire or extract with difficulty)

Source: wiktionary.org