一切經音義 7.59

7.59

陽焰（熱時遙望地上屋上陽氣也似焰非焰故名陽焰如幻如化）。

Mirage (陽焰; the shimmering heat vapour seen from afar upon the ground or on roofs during hot times; it resembles flames yet is not flames, hence called 'vapour flame' (mirage); it is like an illusion, like a phantom).