noun
Meaning 1
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.
Definition source: English Wiktionary via Wiktextract
Usage: countable, uncountable
Topics: chemistry, geography, geology, mineralogy, natural-sciences, physical-sciences
No example sentence was provided for this meaning.
Meaning relationships
Synonyms: none provided
Antonyms: none provided