biarcuate
/ˌbaɪˈɑːkwət/Definitions
1. adjective
having two arches, especially two arches on the back of an animal’s head
“The biarcuate shape of the fossil’s skull revealed a unique characteristic of the ancient species.”
2. verb
to form two arches, especially two arches on the back of an animal’s head
“The evolution of the species led to the biarcuate development of its skull.”