Reuleaux triangle

Spelling & Dictionary Insight

The English entry for Reuleaux triangle is 17 letters long, classified as a noun. 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: "A figure consisting of three circular arcs, each centered on the intersection of the other two.".

No misspelling variants are generated for Reuleaux triangle in our index, suggesting the orthography follows predictable English patterns. 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: Named after Franz Reuleaux, 19th-century German engineer, who used Reuleaux triangles in his machine designs. 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 Reuleaux triangle, spelled R-E-U-L-E-A-U-X- -T-R-I-A-N-G-L-E, and any other sequence of those letters, regardless of how natural it feels, is a misspelling in standard orthography.