corundum

Spelling & Dictionary Insight

The English entry for corundum is 8 letters long, classified as anoun, and transcribed in the International Phonetic Alphabet as /kəˈɹʌn.dəm/. It sits outside the most-frequent rank tiers, which is often why uncommon words generate more spelling variants per reader.The dominant gloss from Wiktionary reads: "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.".

No frequent misspelling variants are recorded for corundum in our index, suggesting the orthography either follows predictable English patterns or the word is uncommon enough that typo corpora lack signal.It is not paired with a close-neighbour confusable in our dataset, which tends to mean the word is visually distinctive enough to stand on its own.

Etymologically, the entry records: From Tamil குருந்தம் (kuruntam, “ruby, sapphire”) First attested in the early 18th century. Root origin matters for spelling because borrowed morphemes (Greek, Latin, Old French, Old English) carry their source-language orthographic conventions into modern English, which is why historical etymology is often the cleanest predictor of whether a cluster like "-ough", "-eau", or "-tion" will appear. For readers arriving here from a spelling check, the authoritative guidance is: the correct English form is corundum, spelled C-O-R-U-N-D-U-M, and any other sequence of those letters, regardless of how natural it feels, is a misspelling in standard orthography.