mirage = سَرَابٌ
سَرَابٌ (saraab) is a mirage. It’s from the verb سَرِبَ (imperfect: يَسْرَبُ , verbal noun: سَرَبٌ ) to flow on the surface of the ground (said of water). The Arabs have a saying: أَخْدَعُ مِنَ السَّرَابِ more deceitful than a mirage. This is often contrasted with the word آلٌ (aal); although some authorities held them to be synonymous, most said that the سَرَاب was a mirage that would cause something to appear on the ground, whereas the آل was a heat shimmer which would cause objects to appear higher than usual. This distinction would appear to be backed up by the root meaning of the two words: as we have already seen, سَرَاب is from the verb سَرِبَ to flow on the ground, whereas آل means originally family, and related to that means a form, figure (of a person, as seen from a distance); as such it would make sense to use this latter to refer to a mirage raised up from the ground, rather like someone seen from a distance is raised in comparison to the flat landscape around him or her. Some said that the آل is a mirage from forenoon ( ضُحًى ) to midday ( ظُهْر ), and the سَرَاب was from midday onwards, though this distinction arose probably due to the commonly observed times for these effects, rather than being part of the linguistic definition. In modern terminology, scientists refer to Superior and Inferior Mirages, which would overlap neatly with the آل and the سَرَب respectively.