noun (plural synsacra /-krə/ or synsacrums)Zoology
An elongated composite sacrum containing a number of fused vertebrae, present in birds and some extinct reptiles.
More example sentences
- The posterior thoracic vertebrae, synsacrum, and hindlimb are pneumatized by diverticula of the abdominal air sacs.
- In most birds, diverticula of the abdominal air sacs pneumatize the posterior thoracic vertebrae and synsacrum later in ontogeny.
- Between the notarium and synsacrum were several dorsal vertebrae that may have provided some level of dorsoventral mobility.
Definition of synsacrum in:
- The US English dictionary