from The Century Dictionary and Cyclopedia
- n. In anatomy, a triangular space or area.
- n. The trigonal space or area at the base of the urinary bladder, whose apex is at the beginning of the urethra, and whose other two angles are at the points of entrance of the ureters into the bladder: more fully called trigonum vesicæ.
- n. A triangular depressed space between the pulvinar and the peduncle of the pineal body; more fully called trigonum habenulæ.
Sorry, no etymologies found.