Definition of arris in English:

arris

noun

Architecture
  • A sharp edge formed by the meeting of two flat or curved surfaces.

    • ‘He noticed the two arris hip tiles that had fallen and saw that two adjacent tiles had become dislodged.’

Origin

Late 17th century: alteration of early modern French areste sharp ridge earlier form of arête.

Pronunciation:

arris

/ˈerəs/