Do US federal government entity names mean anything?

Apart from having different descriptions, the different chunks of the US federal government have different organizational names, for example:

Federal Aviation Administration
Environmental Protection Agency
Federal Bureau of Investigation
Federal Communications Commission
Department of Energy

Do these names reflect meaningful differences in how these entities are organized and/or operated? Or were they just chosen because they sounded good together with the other descriptors for that entity?

FBI name history from Wikipedia:

Bureau of investigation : The BOI’s first official task was visiting and making surveys of the houses of prostitution in preparation for enforcing the “White Slave Traffic Act,” or Mann Act, passed on June 25, 1910. In 1932, the bureau was renamed the United States Bureau of Investigation. The following year it was linked to the Bureau of Prohibition and rechristened the Division of Investigation (DOI) before finally becoming an independent service within the Department of Justice in 1935.[14] In the same year, its name was officially changed from the Division of Investigation to the present-day Federal Bureau of Investigation, or FBI.

so the Bureau part came from the agencies before the FBI

A department is a major executive agency whose head is a cabinet secretary.

A commission is very often an independent agency whose commissioners are appointed for a set term by the president but are empowered to act largely independently of the president’s authority and are independent of any major department.

Administrations, bureaus, agencies, and offices are commonly part of a major department. I’m not sure whether there’s any specific rule as to how they are named.

There are also boards, councils, and services.

Like Ascenray said, it’s a mix. “Department” is the only one that has a specific exclusive meaning: a major organization headed by a Secretary who reports directly to the President (and the Secretary is part of the “Cabinet”). Nothing else can be a “Department”.
“Commission” is usually sort-of independent, headed by Commissioners, but there’s probably some exception. “Bureau” I’d expect to be a sub-part of a Department or other organization (the FBI is part of the Department of Justice), but there could be an independent one for all I know.
“Agency” could be just about anything. The Environmental Protection Agency is a major organization headed by an Administrator who reports directly to the President; it’s not a “Department” only because of historical tradition. There’s probably an “Agency” that’s a sub-part of a traditional Department. “Administration” could also be anything, organization-wise.

To add on, different departments tend to have different conventions on the naming of subordinate offices. For example, the State Department tends to be organized around bureaus (link); whereas in DoD, there’s basically one honkin’ big “office,” three departments, and a mess of quite large agencies that do almost all the work (cite.)

I don’t think that is quite right. There is a Department of the Navy (or Army, etc). Their Secretary does not directly report to the President and are not in the Cabinet.

Isn’t the EPA part of the Department of the Interior? That would be a good reason for it to not be a Department itself.

And NASA is an Administration which I don’t think is part of any department.

The Army, Navy, and Air Force are Departments (with their own Secretaries) but report to the Secretary of Defense.

Bureau is more of a historical name: it was common 100 years ago and usually only agencies created in that era have the name (thus the Federal Bureau of Investigation created in 1908). The more current names are agency and administration.

To Answer the OP:

No. The differences are meaningless, just a function of what someone thought sounded “right” at the time.

Some are descriptive; for example, the FAA administers the process of flying in the country. But it could just as easily have been the Federal Aviation Agency.

No, the EPA is an independent agency.

A Commission is typically (always?) headed by a group of several people, rather than a single Secretary or Administrator. Its official actions to make or change policy would require majority vote.

True now, but historically they were in the cabinet. From the earliest days of the republic, there existed a separate Department of War and a Department of the Navy, both of whose secretaries were in the cabinet. The Department of the Air Force was split off from the Department of the Army in 1947, and the Secretary of the Air Force was also a cabinet-level position. That didn’t last long, and in 1949 the three secretaries of the service departments lost their positions in the cabinet and were replaced by the newly created Secretary of Defense.

I was going to ask a similar question regarding “Secretaries,” “Undersecretaries,” “Assistant Secretaries,” and “Deputy Secretaries.” Notwithstanding my doubts that Deputy Secretaries do not carry a tin star, cowboy hat, nor a cap gun as they wander their organizations’ halls, I always wondered if there was some pecking order to the bureaucratic titles.

Assistant Deputy Undersecretary of the Department of Circumlocution Agency.

In the U. S. Department of State it goes—

  1. Secretary
  2. Deputy Secretary (a “deputy” is someone empowered to act with the full authority of an official—a deputy sheriff can exercise the full authority of the sheriff in the sheriff’s absence)
  3. Under Secretary
  4. Deputy Under Secretary
  5. Assistant Secretary
  6. Deputy Assistant Secretary

To be specific. The EPA is a separate agency. It isn’t an independent agency like the Federal Trade Commission or Federal Communications Commission or the Securities and Exchange Commission are independent.

The president can hire and fire the head of the EPA at will. That’s not true of independent agencies.

Typically, a “Deputy XXX” is a second-in-command for the XXX (“Executive Officer” in military terms) more or less in the same office and at the same level, and not really directly in the chain of command. So a Deputy Pooh-bah would work with the Pooh-bah, maybe in a room right next to the Pooh-bah; together, they’d oversee the Under-Poohs. Each Under-Pooh might have a Deputy Under-Pooh who would work with the respective Under-Pooh in their offices. And the Under-Poohs (working with their Deputies) would oversee Assistant Under-Poohs (each of which could again have a Deputy Assistant Under-Pooh working with them).

In some cases, usually below the Secretary level, a “Deputy XX” might be a career civil servant, while the XX is a political appointee. It’s up to the Pooh-bah herself how to divide responsibilities between her and her Deputy; often (especially where the Deputy is career) the Deputy deals with the administrative aspects of running hte office, while the XX does more big-picture and publicity stuff.

Now that makes sense. I just never heard it in terms I understand like that.