Okay thanks for letting me know!
I think I have noticed this also. A drowned threw a trident at me while I was crossing a river, and when I looked for the drowned to kill it, all I could find was a drowned with a fishing rod.
When you fill them, are you using a bucket or a bottle? You are holding a bottle in the screenshot.
I found an earlier post that recorded this bug. Nevermind.
Something similar happened to me also, except the screen would go white. When I reloaded the world, it was fixed.
From my experience the game thinks its a swear word and censors it.