It certainly is. That’s why, in England at least, the wife of an Earl is a Countess.
The Commanding Officer of a USCG cutter or USN ship is the Captain whether he or she is an O-6 or not. And there was the time that he was the only officer addressed or referred to as Captain also. Another O-6 aboard would be addressed as “Commodore” and a USMC Captain (O-3) in charge of the marine detachment would be called “Major” because there was only one Captain aboard the ship and it would be disrespectful to address him as Lieutenant (USMC O-2, USN O-3).
But they don’t do that as much anymore. The CO is still The Captain, but on a CVN (carrier) now the Executive Officer, Chief Engineer, and the Air Wing Commanders (more than one) are all O-6’s now. But they are all subordinate to the CO. Oh, and the Admiral who commands the Carrier Group and lives on the carrier probably has an O-6 or two on his staff. So the USN O-6’s are Captains and if the senior marine aboard is an O-3 he’s a Captain too now.
So they are peers among Peers?
My God, the press is going to have him for breakfast! They’ll eat him alive, I tell you!
They’ll revoke his crunch berries.
So, fine, a captain has four stripes. So who says a “Cap’n” doesn’t have three?
General Motors too.
Think about all the Colonels of corn General Mills has promoted.
Of course, King Vitaman was forced to abdicate decades ago.
Suspicions abound that Lucky the Leprechaun is really just a gnome (his Irish accent is obviously phony).
And Sonny the Cuckoo Bird only PRETENDED to be insane, to evade the draft.
And did you ever wonder what happened to the Alpha-Bits mailman? He’s in jail- went postal and shot all his colleagues (including King Linus the Lion-Hearted)
And Quisp was deported- he was an illegal alien.
Looks like an Army captain here.
It’ll be a cereal killing.
Apparently I am out of uniform 
Capt
Release the Kraken!
Y’all are funny! At least, you sure think so.
I read that, in addition, any Army or Marine captains who happen to be aboard are customarily referred to as “Major”, because it just doesn’t do to have multiple Captains. Is this true?
And what do they do on a ship where the Captain is a Commodore? Or does that never happen? What about when there are other Navy Captains aboard (as on a flagship, the Admiral’s staff would certainly have some)?
Naaah, you’re fine. Rodenberry always insisted that StarFleet was not a military organisation.
There are no more commodores in the U.S. Navy, alas - instead they have IMHO the single most goofy U.S. rank, “rear admiral (lower half)”: Rear admiral (United States) - Wikipedia
Capt. Kirk wore two-and-a-half stripes on his TOS Starfleet uniform cuffs, not four: http://www.badassoftheweek.com/kirk.jpg
they are often the butt of jokes.
I bet they feel quite the ass.
No more rank of commodore, but they can be commodore (position) of a squadron. Mode of address is still “Captain” AFAIK.
As for Rear Admiral Lower Half, some time ago I did a post going on ad tedium as to how we got to that – I’m on my mobile right now so I can’t stop to search and link but if you look up that plus my username as search terms you may find it. Let’s just say that when they came up with it there was a valid reason to call it that.
Re: Rear Admiral Lower Half…
Somewhere in the Pentagon there’s a list of Rear Admirals. It’s a numerical list going by their ratings. Time in grade, efficiency ratings, awards and citations, etc. If you’re in the upper half of the list, you’re a Rear Admiral Upper Half and you wear 2 stars, get O-8 pay, and your next promotion is to Vice Admiral (3 stars, O-9). And if you’re on the lower half of the list, you’re a RAdm Lower Half (1 star, O-7) and your next promotion is to RAdm Upper Half. I never thought the rank differences between the 3 lower Flag or General Officer grades only matter to other Admirals or Generals.
For a long time, the USCG and USN didn’t have the two grades of R Adms wear different rank insignia. That lasted until enough Brigadier Generals found out they were calling R Adms lower half “Sir” and enough Major Generals found out lousy O-7’s were calling them “Bob” or “Jimbo” instead of “Sir.”