Pronunciation: (yOO"nē-ak'sē-ul), [key]
1. having one axis.
2. Crystall.(of a crystal) having one direction in which double refraction does not occur.
3. Bot.(of a plant) having a primary stem that does not branch and that terminates in a flower.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.