transmission
US /trænˈsmɪʃ.ən/
UK /trænˈsmɪʃ.ən/

1.
the act or process of transmitting something, or the state of being transmitted
:
•
The transmission of data over the internet is very fast.
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Disease transmission can be prevented by good hygiene.
2.
a mechanism in a vehicle that transmits power from the engine to the driving wheels
:
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My car needs a new transmission.
•
The mechanic checked the car's automatic transmission.