peritroch
/pərɪˈtrɒk/Definitions
1. noun
A minute spiral ridge or groove on the surface of a cell, especially a sperm cell.
“The scientist used a microscope to study the peritroch on the sperm cell under examination.”
2. noun
A microscopic spiral ridge or groove on a pollen grain.
“The peritroch on the pollen grain played a crucial role in its fertility and germination process.”