Liddell-Scott-Jones

αἴθριος (aithrios) open air ^G:A

αἴθριος, ον,

clear, bright, of weather, αἰθρίου ἐόντος τοῦ ἠέρος[Refs 5th c.BC+]; αἴ. πάγος clear frost, [Refs 5th c.BC+]; falsa lectio in [Refs]

__2 epithet of Ζεύς, [Refs 4th c.BC+]; of winds which cause a clear sky, h. Ap.[Refs 4th c.BC+]; especially of the North wind,[Refs]
__II kept in the open air, στέφη[Refs 5th c.BC+]
__III αἴθριον, τό, adaptation of Latin atrium to a Greek sense, [Refs 1st c.AD+]