Formal:
* Bald: This is the most common and straightforward way to describe someone with no hair.
* Hairless: This is a more clinical term, often used in medical or scientific contexts.
Informal:
* Slick: This term is often used playfully, especially when referring to a man who is bald.
* Skinhead: This term refers to a person who shaves their head completely.
Other options:
* Alopecic: This term refers to a person who suffers from alopecia, a medical condition that causes hair loss.
* Depilated: This term refers to someone who has had their hair removed by artificial means, such as shaving or waxing.
It's important to be mindful of the connotations associated with each term and to choose the one that best fits the situation and your intended meaning.
It's also important to remember that being bald is perfectly normal and there is no need to use any term in a derogatory or offensive way.