Dictionary
pen•ta•va•lent
Pronunciation: (pen"tu-vā'lunt, pen-tav'u-), [key]—
adj. Chem.
1. having a valence of 5:
pentavalent arsenic.
2. quinquevalent (def. 2).
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.