# Definition of *hypocycloid* in English:

## hypocycloid

### Pronunciation /ˌhīpəˈsīkloid/ /ˌhaɪpəˈsaɪklɔɪd/

### noun

Mathematics

The curve traced by a point on the circumference of a circle which is rolling on the interior of another circle.

*‘It was also investigated by Steiner in 1856 and is sometimes called Steiner's hypocycloid.’*

*‘The present invention relates to a hypocycloid gear assembly used in internal combustion engines.’**‘If the describing circle is half the diameter of the pitch circle, the hypocycloid is a radial straight line.’**‘Similarly, the vertexes of an hypocycloid are the points on the curve that coincides with an inscribed circle.’**‘The present invention relates to a hypocycloid engine assembly which may be used in internal combustion engines.’*