'Cambium' definitions:

Definition of 'cambium'

From: WordNet
noun
A formative one-cell layer of tissue between xylem and phloem in most vascular plants that is responsible for secondary growth
noun
The inner layer of the periosteum

Definition of 'Cambium'

From: GCIDE
  • Cambium \Cam"bi*um\, n. [LL. cambium exchange, fr. L. cambire to exchange. It was supposed that cambium was sap changing into wood.]
  • 1. (Bot.) A series of formative cells lying outside of the wood proper and inside of the inner bark. The growth of new wood takes place in the cambium, which is very soft. [1913 Webster]
  • 2. (Med.) A fancied nutritive juice, formerly supposed to originate in the blood, to repair losses of the system, and to promote its increase. --Dunglison. [1913 Webster]