Sailors have unique ways to get under each other's skin.
A comment that may seem harmless to an outsider might be a jab to a shipmate. Just add the word "SHIPMATE" to the insult to take it to the next level. Consider yourself warned and use the following sailor insults at your own risk:
140 sailors go down, 70 couples come back.
Submariners hate this one, used by surface sailors to mock submariners going on deployment.
"Unsat"
"Unsat" is short for unsatisfactory. This is not derogatory, but sailors hate the term being used to describe their work, something they did, their appearance -- anything. When the chief says, "Shipmate, your haircut is unsat," sailors know they'd better do something about it.
B.U.B.
Stands for 'Barely Useful Body.' Sometimes used in a derogatory manner, but sometimes used to describe someone who's been injured or physically unable to perform 100 percent. Either way, it hurts the ego.
The Bulls--t flag
This is an imaginary flag someone raises when they believe that what you're saying is pure bulls--t. It's usually phrased, "I am raising the bulls--t flag on that one."
Buttshark
Otherwise known as a brown-noser or butt snorkeler. This is a person who tries too hard to buddy up with another – usually a superior – to gain favor.
Check Valve
Also known as a "one-way check valve." This is a term used mostly by submariners and surface ship snipes to describe someone who does things for him or herself but doesn't reciprocate.
C.O.B.
This one has several different derogatory meanings to describe the senior enlisted person aboard a ship: Chief of the Boat, Crabby Old Bastard, and Clueless Overweight Bastard.
F.L.O.B.
It stands for Freeloading Oxygen Breather. This is a term mostly used by submariners to describe someone who is not carrying their share of the load.
"How's your wife and my kids?"
A phrase used to get under the skin of sailors from opposite crews.
Joe Navy
A derogatory term used for a lifer with no life outside the Navy who engages in a lot of buttsharking.
Pecker Checker
This is the official, unofficial term used to describe a Navy doctor or corpsman. Sailors know better than to address the doc this way before a physical.
By no means is this a complete list, so feel free to add more terms in the comments below.