Hey Wanikani!
I just have a small suggestion for the definition of 水兵. As I’m in the Navy, it pains me inside to every time have to type, “navy soldier” as the definition. I’m sorry to report that there is no such thing as a “navy soldier”, it’s a called a sailor! Solider usually specifically refers to someone in the Army, not the Navy. If you could fix the definition or add it, it would make me feel much better inside.
Thanks!
Andrew
The best way to reach them for these kinds of things, despite the existence of this forum section, is through email, since they are a small team. If you send them an email at hello@wanikani.com I would imagine it has a good chance of being changed.
From my understanding a sailor isn’t necessarily part of the armed forces. If they replace the meaning with “sailor” it may convey the idea of someone who does it for leisure. Just my 2 cents.
That can possibly be addressed by adding something like “naval sailor” or “sailor in the navy.”
It’s not really an excuse for using a word that doesn’t apply at all.
Clearly “water soldier” is the correct term here. 
But seriously, “seaman” is already accepted as a synonym, and while you’re waiting for Something to be Done, you’re free to add your own synonyms too.
Seaman is probably the best choice since it maps directly to the Japanese Naval Enlisted ranks of E-1 to E4:
The category as a whole is called 水兵, Seaman or Enlisted Seaman, for ranks below Petty Officer.
Although Water Soldier does have a nice ring to it. lol
Something similar to this that comes to mind is 禅僧 which has only 1 meaning as zen priest, when it probably be more correct to say zen monk.
Are all Zen Monks also Priests? Or are Priests a specific rank within 仏教? If so, which one does the word refer to?
I think the words are interchangeable. I have only ever heard of zen monks, but I think priest would mean the same thing.
I think you meant 水兵?
Hmm so this is more complicated than at first glance.
In English, Zergzurg is right. It could be used to refer to either a civilian or a Navy sailor, however generally it’s pretty easy to tell which you are referring to based on context.
Usually we do not use the word “seaman” to broadly refer to Navy Sailors as “seaman” is a specific rank in the US Navy. Also as was already pointed out in the gif, seaman has other “fun” meanings which is why we tend to avoid using it to refer to all Navy sailors.
Talking to my JMSDF friends, 水兵 is an older word which is not really used anymore. When Japanese refer to the JMSDF they usually use 海自、an abbreviation for 海上自衛隊. The JMSDF use 海士 internally to refer to other JMSDF.
All that to say…I still wouldn’t use “Navy Solider” as the definition, rather Navy Sailor. I’ve now spent way to much time researching this. 
So, what is the difference between Marine and Navy?
I’ve thought of that.
I have literally never heard “navy soldier” used in my life. 99% of the time, it’s just sailor, not Navy anything.
I have “Sailor” added as a synonym of course. I’m not memorizing or typing “Navy soldier”
P.S. Navy family here, so I hear it a lot.
I agree. I added sailor as a user synonym.
I mean if you live in the context of the navy then it’s not really that strange that you would hear the preferred terms
Marines are part of the army. Generally, they’re ground troops who are particularly trained in jumping from ships onto beaches to engage in combat. Think the opening scene of Saving Private Ryan.
The Navy sails the ships.
I think the point of bringing it up is that those words are not the preferred term in any context. Yes, each user is free to add a synonym (sailor) if they know a word in a different context (in English, the generic title for US Navy personnel is Sailor, Army is soldier, Marine Corps is Marine, Air Force is Airmen). But the reason for having the discussion / contacting WK is that there actually is no context or situation anyone would ever, ever say “Navy soldier” in English, especially if they’re familiar with the culture.
Of course there is, otherwise it wouldn’t be the definition on WK. I think to people who aren’t familiar with the military (yes I am including the navy in the military) it is an expression that makes sense, much more sense than solely “sailor” would make. I’m not saying that “navy soldier” is correct, but you can’t say that it’s not a term that’s used when there is evidence right in front of you
I don’t know if Saida’s original question was about US forces or militaries generally, but, the first sentence here is not accurate.
For US forces, Marines are members of the Marine Corps, which is a separate branch from the Army. Confusingly, the Marine Corps is a part of the Department of the Navy–the Navy and the Marine Corps are much more closely related than either is to the Army. (The fact that military operations on land can involve using the Marine Corps and the Army together does make it seem like they’re more related than they are, though.)
The short answer for Saida is that they’re just separate branches of the US military.