Examples from the Web for biconcave
It was composed of vermiform rods 1⁄1000 inch in width, and breaking up into cylindrical segments with biconcave ends.Cruise of the 'Alert'|R. W. Coppinger
The vertebral centra are opisthocoelous or biconcave, and there are numerous precaudal vertebrae.
The vertebrae are solid and may be opisthocoelous, biconcave, or flat.
It had also the curious and old-fashioned peculiarity of biconcave vertebræ, like those of fishes and some reptiles.The Chain of Life in Geological Time|Sir J. William Dawson
The vertebræ are very numerous and biconcave as in ordinary fishes.A Guide to the Study of Fishes, Volume 1 (of 2)|David Starr Jordan