xié​yīn

harmonic

谐音 (諧音) xié​yīn
harmonic noun
a component of a complex sound or an oscillation whose frequency is an integral multiple of the fundamental frequency

In acoustics, the composition of harmonics determines the timbre of an instrument.

homophone noun
words or characters that have the same or similar pronunciation but different meanings

Many Spring Festival couplets use homophones to express auspicious meanings, such as 'fish' and 'surplus.'

Frequency

Movie subtitles
3.10 per million appears in 1% of films
Written text
1.57 per million

Sources

Definitions
CC-CEDICT