Pronunciation: [ɹˈat ɹˈʌn] (IPA) 
The term "rat run" is spelled phonetically as /ræt rʌn/. This refers to a narrow, often hidden passage or pathway that is typically used as a shortcut for vehicles or pedestrians to avoid traffic or congestion. The word "rat" is spelled with an 'r' sound followed by a short 'a' sound, while the word "run" is spelled with a short 'u' sound. The term is commonly used in urban areas, particularly in the UK and Australia.
A "rat run" refers to a lesser-known or unofficial route used by drivers to avoid congested main roads or highways, particularly during peak traffic periods. This term is predominantly used in urban and suburban areas, where traffic congestion is more prevalent. Rat runs are often shortcuts through residential neighborhoods, backstreets, or narrow lanes that are not designed to accommodate high volumes of traffic.
The term "rat run" alludes to the behavior of rats, which are known for darting through small and obscure pathways. Similarly, drivers utilizing rat runs are seeking alternative, less crowded routes to swiftly navigate through traffic, often in an attempt to reach their destination more quickly.
Although rat runs may provide relief from heavy traffic, they can have negative consequences for the neighborhoods they traverse. Increased traffic volume on residential streets can lead to noise pollution, diminished safety for pedestrians and children, and damage to infrastructure not designed to accommodate high vehicle flow. Consequently, some communities may implement traffic-calming measures or restrictions to deter rat run usage.
The popularity of rat runs has been amplified in recent years due to advancements in navigation technology, such as GPS applications. These apps often provide real-time traffic updates and suggest alternative routes to users, leading to increased awareness and utilization of rat runs. Consequently, the debate surrounding their impact on cities still persists, calling for urban planning initiatives and transportation policies to strike a balance between relieving congestion and preserving the livability of residential areas.
The term "rat run" originated in the late 19th century in the context of rats or rodents, specifically their behavior and movement. However, its usage has evolved over time to refer to human behavior instead. The word "rat" itself can be traced back to Middle English, deriving from the Old English word "ræt".
In the context of humans, a "rat run" refers to a street or route that is used by drivers as a shortcut or alternative to main roads during congested periods. These often tend to be smaller, less-traveled streets in residential or urban areas. The term suggests that these routes are used by drivers in a manner similar to how rats navigate through small or hidden passages to avoid detection or obstacles.
The etymology of "rat run" in its current sense as a shortcut for drivers is a metaphorical extension of the word "rat".
