'Pentoxide' definitions:
Definition of 'pentoxide'
From: WordNet
noun
An oxide containing five atoms of oxygen in the molecule
Definition of 'Pentoxide'
From: GCIDE
- Pentoxide \Pen*tox"ide\, n. [Penta- + oxide.] (Chem.) An oxide containing five atoms of oxygen in each molecule; as, phosphorus pentoxide, P2O5. [1913 Webster]