Anat. and Zool. Pl. -antra. [mod.L., f. Gr. ζυγόν yoke + ἄντρον cave.] A double cavity on the posterior side of the neural arch of each ordinary vertebra in serpents and some lizards, into which the zygosphene of the next vertebra fits.
1854. Owen, in Orr’s Circ. Sci., Org. Nat., I. 197. This wedge [sc. the zygosphene] is received into a cavity (the ‘zygantrum’) excavated in the posterior expansion of the neural arch.
1888. Rolleston & Jackson, Anim. Life, 73.
