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Medical Term:


Pronunciation: lan'tha-nidz


Those elements with atomic numbers 57–71 that closely resemble one another chemically and were formerly difficult to separate from one another. they vary in the electrons in the 4f orbital.

Synonym(s): rare earth elements

[lanthanum, first element of the series]

© Copyright 2017 Wolters Kluwer. All Rights Reserved. Review Date: Sep 19, 2016.