D defs.my
Entry 1 sense Webster, 1913

Vanadious

· Va·na·di·ous · IPA
01 a. Pertaining to, or containing, vanadium; specifically, designating those compounds in which vanadium has a lower valence as contrasted with …
  1. 1.
    Pertaining to, or containing, vanadium; specifically, designating those compounds in which vanadium has a lower valence as contrasted with the vanadic compounds; as, vanadious acid. Usually written vanadous.(Chem.) Also: vanadous