inradius
|in-ra-di-us|
/ɪnˈreɪdiəs/
radius of an inscribed circle
Etymology
'inradius' is formed from the Latin prefix 'in-' meaning 'in, on, into' and the Latin noun 'radius' meaning 'ray' or 'spoke'.
'radius' is a Latin word that entered English as 'radius'; the compound 'inradius' is a modern mathematical formation combining 'in-' + 'radius' to denote a radius directed inward (the radius of an inscribed circle).
Originally the components literally meant 'in' + 'ray/spoke'; over time the compound came to be used specifically in geometry to mean 'the radius of an inscribed circle.'
Meanings by Part of Speech
Noun 1
the radius of an inscribed circle (incircle) of a polygon or triangle; the distance from the center of the incircle to a side.
The inradius of a triangle can be found using the formula r = A/s, where A is the area and s is the semiperimeter.
Synonyms
Antonyms
Last updated: 2025/12/17 14:51