corundum
An extremely hard mineral, a form of aluminum oxide with the chemical formula Al₂O₃,…An extremely hard mineral, a form of aluminum oxide with the chemical formula Al₂O₃, that occurs in the form of the gemstones sapphire and ruby; it is used as an abrasive.
» Sapphire is the blue form of corundum.
Meaning
1 senses(countable, uncountable)An extremely hard mineral, a form of aluminum oxide with the chemical formula Al₂O₃, that occurs in the form of the gemstones sapphire and ruby; it is used as an abrasive.
Korund
кору́ндkorúnd
кору́ндkorúnd
very hard mineral used as an abrasive
Examples
6 sentencesSapphire is the blue form of corundum.
Ruby is the red form of corundum.
Several precious stones are a form of corundum.
Corundum is a form of aluminum oxide.
Corundum comes in all colors of the rainbow.
Translations
9 languagesBy meaning 1
By meaning 1
By meaning 1
Origin
From Tamil குருந்தம் (kuruntam, “ruby, sapphire”) First attested in the early 18th centuryFrom Tamil குருந்தம் (kuruntam, “ruby, sapphire”) First attested in the early 18th century.
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Forms
plural: corundumsSynonyms
1 synonyms- very hard mineral used as an abrasive:corundom
Word family
4 related wordsLessons for this word
1 lessons- A1Countable and uncountable nouns — Because it can be uncountable