RECOMMENDED LESSONS: Runoff Runoff is precipitation that did not get (infiltrated) absorbed into the soil, or did not evaporate, and therefore made its way from the ground surface into places that water collect. Runoff causes erosion, and also carry chemicals and substances on the ground surface along to the rivers where the water ends up.
Noun. 1. obelisk-a stone pillar having a rectangular cross section tapering towards a pyramidal top. pillar, column-a vertical cylindrical structure standing alone and not supporting anything (such as a monument).
Cleopatra's Needle is a red granite obelisk. The Cleopatra's Needle in Central Park is one of three; there also is one in Paris and one in London, which is one of a pair with the New York obelisk. Each obelisk is approximately 68â69 feet tall and weigh about 180 tons.