Definitions

1. adjective

Relating to or forming the synsacrum, a fusion of the sacrum and the first few caudal vertebrae in some vertebrates.

“The synsacral structure of the early dinosaur is an interesting example of evolutionary adaptation.”

2. noun

The synsacrum, a fusion of the sacrum and the first few caudal vertebrae in some vertebrates.

“The fossil of a synsacral reptile has provided valuable insights into the evolution of the vertebrate skeleton.”