General "fool":
* Дурак (durak) - This is the most common and neutral word for "fool." It can be used in a variety of contexts, from playful teasing to serious criticism.
* Глупец (glupets) - This word has a slightly more negative connotation than "durak" and implies a lack of intelligence or common sense.
Other options:
* Идиот (idiot) - This word is more severe and often used to describe someone who is completely lacking in intelligence or reason.
* Безумец (bezumets) - This word implies that someone is mentally unstable or delusional.
* Олух (olukh) - This word is more playful and humorous than the others, but can also be insulting.
* Простак (prostak) - This word describes someone who is naive or simple, but not necessarily stupid.
The best way to choose the right word depends on the context and your intended meaning.
Important Note: It's important to be mindful of the situation and your relationship with the person you are talking about when using these words, as they can be offensive.