alkaline earth

American  

noun

Chemistry.

1. any of the oxides of barium, radium, strontium, calcium, and, sometimes, magnesium.

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alkaline earth British  

noun

1. Also called: alkaline earth metal.   alkaline earth element.  any of the divalent electropositive metals beryllium, magnesium, calcium, strontium, barium, and radium, belonging to group 2A of the periodic table

2. an oxide of one of the alkaline earth metals

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Etymology

Origin of alkaline earth

First recorded in 1810–20

Example Sentences

The only result that popped up pertained to chemistry: specifically, to the periodic table and the atomic numbers of the alkaline earth metals.

From New York Times

A silvery, alkaline earth metal called strontium comes in different versions, or isotopes, each with a different atomic mass.

From Scientific American

Liu, Y., Merinov, B. V. & Goddard, W. A. Origin of low sodium capacity in graphite and generally weak substrate binding of Na and Mg among alkali and alkaline earth metals.

From Nature

In that chart, helium is placed above the alkaline earth elements, contrary to its usual position as a member of the noble gases family in conventional tables.

From Scientific American

Optical lattice clocks with alkaline earth atoms provide one of the most stable time-keeping systems.

From Science Magazine