taximeter
noun
taxi·me·ter ˈtak-sē-ˌmē-tər 
: an instrument for use in a hired vehicle (such as a taxicab) for automatically showing the fare due
Example Sentences
Recent Examples on the Web The taxi version also features a single display that integrates navigation, the taximeter, and other important data, such as charging station locations. 
Caleb Miller, Car and Driver, 28 Apr. 2022
Caleb Miller, Car and Driver, 28 Apr. 2022 Word History
Etymology
French taximètre, modification of German Taxameter, from Medieval Latin taxa tax, charge (from taxare to tax) + German -meter
First Known Use
1894, in the meaning defined above