Definitions

1. noun

A tube or canal in a fossil shell, typically connecting the siphuncle of a previous whorl to that of the next whorl, through which the siphuncle is connected to the body whorl, allowing the shell to expel water as it grows.

“The fossil expert examined the siphuncle of the ammonite to determine its age and habitat.”

2. noun

A tube in a spermatozoon that contains the flagellum.

“The spermatozoon’s siphuncle plays a crucial role in fertilization, allowing it to move efficiently through the female reproductive tract.”