1. She has long, blonde hair.

2. She has long, blond hair.
3. He has short blond hair.
4. He has medium-length, blonde hair.

Is blonde only for womem?
Are all correct in the four sentences above?

They are all correct -- except you need a comma in # 3.

Traditionally, blonde referred to women and blond referred to people in general and men. However, that usage seems to be changing in favor of using blond for both genders.

The terms "blonde" and "blond" can be used interchangeably to describe light-colored hair. The spelling "blonde" is commonly used for women, while the spelling "blond" is more commonly used for men. However, this distinction is not strict, and both spellings can be used for either gender.

With regards to the sentences you provided:
1. "She has long, blonde hair." - This sentence is correct and uses the preferred spelling for women.
2. "She has long, blond hair." - This sentence is also correct, but uses the less commonly used spelling for women.
3. "He has short blond hair." - This sentence is correct and uses the preferred spelling for men.
4. "He has medium-length, blonde hair." - This sentence is correct and uses the preferred spelling for men.