lithium

n. (Li) soft metallic element which is the lightest of all metals (Chemistry)

Lithium is a chemical element with the symbol Li and atomic number 3. It is a soft alkali metal with a silver-white color. Under standard conditions, it is the lightest metal and the least dense solid element. Like all alkali metals, lithium is highly reactive, corroding quickly in moist air to form a black tarnish. For this reason, lithium metal is typically stored under the cover of oil.
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Noun
1. a soft silver-white univalent element of the alkali metal group; the lightest metal known; occurs in several minerals
(synonym) Li, atomic number 3
(hypernym) metallic element, metal
(substance-holonym) lepidolite

n. lithium, metallic element which resembles sodium

n. lithium, soft metallic element which is the lightest of all metals (Chemistry)