The term 'MIRAGE SIGHT' is a combination of two words, 'MIRAGE' and 'SIGHT'. MIRAGE is an optical illusion caused by atmospheric conditions, which makes distant objects appear to shimmer or wave. SIGHT is the ability to perceive with the eyes. Therefore, the term 'MIRAGE SIGHT' refers to the phenomenon of seeing a MIRAGE. The crossword solution for this term is 'OASIS', which is a place in a desert where water is found. An OASIS is often seen as a MIRAGE due to its rarity in the desert environment.