Where did the "wheel" group get its name?
The Jargon File has an answer which seems to agree with JanC.
wheel: n. [from slang ‘big wheel’ for a powerful person] A person who has an active wheel bit...The traditional name of security group zero in BSD (to which the major system-internal users like root belong) is ‘wheel’...
A wheel bit is also helpfully defined:
A privilege bit that allows the possessor to perform some restricted operation on a timesharing system, such as read or write any file on the system regardless of protections, change or look at any address in the running monitor, crash or reload the system, and kill or create jobs and user accounts. The term was invented on the TENEX operating system, and carried over to TOPS-20, XEROX-IFS, and others. The state of being in a privileged logon is sometimes called wheel mode. This term entered the Unix culture from TWENEX in the mid-1980s and has been gaining popularity there (esp. at university sites).
As others have said, it comes from the term "Big Wheel". I think many of us are not familiar with this term because, according to at least one site, it became a popular expression after World War Two:
Big wheel is another way to describe an important person. A big wheel may be head of a company, a political leader, a famous doctor. They are big wheels because they are powerful. What they do affects many persons. Big wheels give the orders. Other people carry them out. As in many machines, a big wheel makes the little wheels turn.
Big wheel became a popular expression after World War Two. It probably comes from an expression used for many years by people who fix the mechanical parts of cars and trucks. They said a person "rolled a big wheel" if he was important and had influence.
For those like me who were born in the 1980s, we may find the following a closer cultural reference for a Big Wheel:
It comes to us from BSD. This is verifiable. But where did it begin?
Here is a un-verified, but maybe verifiable explanation- BSD got it from the TOPS-20 O/S.
http://lists.freebsd.org/pipermail/freebsd-chat/2003-December/001725.html
