Fear of trains the social norms of a realistic fear, this anxiety may be classified as a specific phobia about trains. "Campbell's Psychiatric Dictionary" puts fear of trains under the "vehicle phobia", together with fears of boats, airplanes, automobiles, and other forms of transportation. A 1913 short story "Terror" by Jun'ichirō Tanizaki is a first-person narrative of a young man suffering of the morbid fear of travel in trains and streetcars. Tanizaki uses the German word , "railroad sickness". Other travel-related anxieties include: Other transport-related disorders include: Fear of trains The fear of trains is anxiety and fear associated with trains, railways, and
Irrational number Irrational number In mathematics, the irrational numbers are all the real numbers which are not rational numbers, the latter being the numbers constructed from ratios (or fractions) of integers. When the ratio of lengths of two line segments is an irrational number, the line segments are also described as being "incommensurable", meaning that they share no "measure" in common, that is, there is no length ("the measure"), no matter how short, that could be used to express the lengths of both of the two given segments as integer multiples of itself. Among irrational numbers are the ratio of a circle's