What does frequency mean in science term?

Answer 1

Frequency, referring to sound, is the amount of complete waves every second that produce sound.

For example: High pitched sounds, like the sound that whistles make, have a high frequency (lots of waves per second). And Low pitched sounds like the sound that a subwoofer makes have a low frequency (Not so many waves per second)

The average human can hear from 20hz (cycles per second) up to around 20,000hz (cycles per second)

Answer 2

Answ2. Frequency is the number of times something happens in a stated period.

"The Moon rotates round the Earth at a frequency of once every twenty-eight days."

"The FM radio band sits around frequencies of 100 MHz. (100 000 000 Hertz per second, or 100 000 000 cycles per second.)"