瑜伽師地論略纂 9.41

9.41

論解十五種所作變異，第八、寒熱變異中云言「乾語」者，謂熱故，言語時乾，如世人云乾語，濕變也。

The treatise, explaining the fifteen kinds of produced transformations, in the eighth, transformation of cold and heat, states "dry speech." This means that due to heat, when speaking it is dry; as worldly people say "dry speech," this is a transformation of moisture.