The term 'apparent horizon' is a crossword solution for the word 'SKYLINE'. Apparent horizon is a term used in astronomy and meteorology to describe the line that appears to separate the sky from the Earth's surface when viewed from a certain point. It is also known as the visible horizon, geometric horizon, or local horizon. The apparent horizon is affected by the curvature of the Earth, the observer's distance from the Earth's surface, and the refraction of light in the atmosphere.