猿 is one of those cases when an error was made as Chinese characters were absorbed into the Japanese language during the 5th century.

In Japanese, this means monkey.
In Chinese, this means ape.

The Japanese word for ape means monkey in Chinese, so you can see how they were simply reversed.

猿拳 is the Japanese martial arts title, “Monkey Fist,” referring to Monkey-Style Kung Fu.

猿拳 is very similar to a Chinese term that uses a different first character (the characters for ape and monkey were reversed when Japan borrowed Chinese characters, so this would be “Ape Fist” if a Chinese person read it).

猴 is the monkey character in Chinese.
猴 means ape in Japanese due to an error made long ago as Japan absorbed Chinese characters.

If you were born in the year of the monkey, you . . .

Are smart, brave, active, and competitive.
Like new things.
Have a good memory.
Are quick to respond
Have an easy time winning people's trust.
Are, however, not very patient.

See also our Chinese Zodiac page.

Note: This character does have the meaning of monkey in Korean Hanja but is not used very often.

金剛 can translate as adamantine from Chinese, Japanese, and old Korean.

Other meanings and translations can include diamond, thunderbolt, Indra's indestructible weapon, a Buddhist symbol of the indestructible truth, Vajra (a mythical weapon), guardian deity, hardness, indestructibility, power, the least frangible of minerals.

The Chinese pronunciation of “Jīn Gāng” became the loanword used in English as “King Kong.” You can see King Kong as the indestructible ape guardian deity depending on how you read the story.