The word geek is a slang term, noting individuals as "a peculiar or otherwise odd person, especially one who is perceived to be overly obsessed with one or more things including those of intellectuality, electronics, etc." Formerly, the term referred to a carnival performer often billed as a wild man whose act usually includes biting the head off a live chicken, bat, snake or bugs. The 1976 edition of the American Heritage Dictionary included only the definition regarding geek shows.

This word comes from English dialect geek, geck: fool, freak; from Low German geck, from Middle Low German. The root geck still survives in Dutch gek: crazy, and in the Alsatian word Gickeleshut: geek's hat, used in carnivals.

Definitions

The definition of geek has changed considerably over time, and there is no longer a definitive meaning. The terms nerd, gimp, dweeb, dork and spod have similar meanings as geek, but many choose to identify different connotations amongst these terms, although the differences are disputed. In a 2007 interview on The Colbert Report, Richard Clarke said the difference between nerds and geeks is "geeks get it done." Julie Smith defined a geek as "a bright young man turned inward, poorly socialized, who felt so little kinship with his own planet that he routinely traveled to the ones invented by his favorite authors, who thought of that secret, dreamy place his computer took him to as cyberspace—somewhere exciting, a place more real than his own life, a land he could conquer, not a drab teenager's room in his parents' house."

Other definitions include:

• A derogatory reference to a person obsessed with intellectual pursuits for their own sake, who is also deficient in most other human attributes so as to impair the person's operation within society.
• A person who is interested in technology, especially computing and new media. Geeks are adept with computers, and use the term hacker in a positive way, though not all are hackers themselves.
• A person who relates academic subjects to the real world outside of academic studies; for example, using multivariate calculus to determine how they should correctly optimize the dimensions of a pan to bake a cake.
• A person who has chosen concentration rather than conformity; one who passionately pursues skill (especially technical skill) and imagination, not mainstream social acceptance.
• A person with a devotion to something in a way that places him or her outside the mainstream. This could be due to the intensity, depth, or subject of their interest. This definition is very broad but because many of these interests have mainstream endorsement and acceptance, the inclusion of some genres as "geeky" is heavily debated. Persons have been labeled as or chosen to identify as physics geeks, mathematics geeks, engineering geeks, sci-fi geeks, computer geeks, various science geeks, movie and film geeks (cinephile), comic book geeks, theatre geeks, history geeks, music geeks, art geeks, philosophy geeks, literature geeks, historical reenactment geeks and roleplay geeks.
• A more recent school of thought sees Nerd as being a derogatory phrase, whilst Geek is simply a description. It is taken to be someone who is an enthusiast, often in things outside of the mainstream spectrum, of note is that in this definition, there is no reference to being socially inept in the slightest.