frequency
n. C / Un. the rate at which something happens over a certain period of time. You use this word to talk about how often an event repeats.
n. the rate at which an event occurs over a given period of time or within a specific population. In physics and acoustics, it measures the number of wave cycles per second.
The frequency of trains on this line increases during rush hour.
Due to the high frequency of accidents at the intersection, the city council decided to install new traffic lights.
As the patient's condition deteriorated, the frequency of his panic attacks increased, prompting the medical team to adjust his medication dosage immediately.
From Latin frequentia, from frequens. By surface analysis, frequent + -cy.
Often followed by the preposition 'of' to specify the event being measured.