عده دور سنج ،سرعت نما،تندى نما،سرعت سنج ،کيلومتر شمار ساعتى علوم مهندسى : تاکومتر معمارى : سرعت سنج روانشناسى : سرعت سنج علوم نظامى : سرعت سنج
a meter fixed to a vehicle that measures and displays its speed(n)
Synonyms: speed indicator
speedometer
Hyponyms: machmeter
Hypernyms: meter
PartMeronyms: automotive vehicle
motor vehicle
PartMeronyms: automotive vehicle
motor vehicle
PartMeronyms: automotive vehicle
motor vehicle
A speedometer or speed meter is a gauge that measures and displays the instantaneous speed of a vehicle. Now universally fitted to motor vehicles, they started to be available as options in the early 20th century, and as standard equipment from about 1910 onwards. Other vehicles may use devices analogous to the speedometer with different means of sensing speed, eg. boats use a pit log, while aircraft use an airspeed indicator.