The term 'geek (out)' is a slang phrase used to describe someone who is overly enthusiastic about a particular topic or activity. The term can also be used to describe someone who is passionate and knowledgeable about a certain subject. The crossword solutions for the term 'geek (out)' are 'NERD' which is a four letter word. A NERD is someone who is highly intelligent and often socially awkward. They are usually passionate about a certain subject and have an extensive knowledge of it.