rhombocele

rhom·boi·dal si·nus

, sinus rhomboidalis
a dilation of the central canal of the spinal cord in the lumbar region.
Synonym(s): rhombocele
Farlex Partner Medical Dictionary © Farlex 2012

rhomboidal sinus

(1) Cavity of septum pellucidum; cavum septi pellucidi [NA6]. 
(2) Terminal ventricle of spinal cord; ventriculus terminalis medullae spinalis [NA6]
Segen's Medical Dictionary. © 2012 Farlex, Inc. All rights reserved.

rhom·boi·dal si·nus

, sinus rhomboidalis (rom-boy'dăl sī'nŭs, rom'boy-dā'lis)
A dilation of the central canal of the spinal cord in the lumbar region.
Synonym(s): rhombocele.
Medical Dictionary for the Health Professions and Nursing © Farlex 2012

rhombocele

(rŏm′bō-sēl) [″ + koilos, a hollow]
The cavity of the rhombencephalon.
Medical Dictionary, © 2009 Farlex and Partners