n. A reddish glow seen near sunset or sunrise on the summits of mountains; specif., a reillumination sometimes observed after the summits have passed into shadow, supposed to be due to a curving downward (refraction) of the light rays from the west resulting from the cooling of the air. [ Webster 1913 Suppl. ]

n. A reddish glow seen near sunset or sunrise on the summits of mountains; specif., a reillumination sometimes observed after the summits have passed into shadow, supposed to be due to a curving downward (refraction) of the light rays from the west resulting from the cooling of the air. [ Webster 1913 Suppl. ]