It is almost impossible for someone to know what you are talking about with a single word in Chinese, if you do not have the Chinese character or any context.
Mandarin Chinese is a tonal language, which means that you need to differentiate whether a word’s tone is flat, goes up, goes down, or dips before rising again (the 4 tones of Chinese). Simply telling someone what the sound of the word is means that you narrow down the options for what a word could mean, but there could still be many different possibilities.
For example, 妈妈骂马吗 would be spelled mama ma ma ma but the tones differentiate the words, and this forms a sentence that asks, “Does mother scold the horse?”
That said, it looks like Chin is capitalized (meaning a name). My best guess is Chin is a last name in Cantonese, not Mandarin Chinese, which would be written as 陈.
If you are talking about how to say the word “chin” in Mandarin Chinese, the body part is known as 下巴.
