See also "ornitho" (relating to birds) and "pter" (wing) creating the term ornithopter for a heavier than air vehicle that flies by flapping its wings. Famously seen in Dune, but I think also back in the day people actually tried to make them, long before aircraft existed.
The german word for aeroplane is similar, "Flugzeug" directly translates to "flying thing".
Helicopter is also fun, "Hubschrauber" translates to "lifting screwer".
I guess for "Flugzeug", 'device' works better but I don't think I have ever thought about it in that way. From my experience usage usually goes more like this: "Pack dein Zeug zusammen wir gehen weiter." which I think best translates to 'Stuff' or 'things'.
Zeug is an interesting word though. It is also used for the harness of a draft animal ("sich ins Zeug legen"), it's bridle ("Zaumzeug"), bed linen ("Bettzeug"), work tools ("Werkzeug") , or as a word for nonsense ("red kein dummes Zeug"). I would say it started, as you said, as a word for device but became a slightly negative word for 'Stuff'.
I dont get it. Is this read from left to right or from right to left? Manga typically reads from right to left, but judging from her reaction neither makes sense... She is not making a "wha-" expression, which indicates that it came before, but she is already turning her head, which indicates that it it came after. WHAT.
I think the intended idea was that she freezes mid-sentence in shock after fully comprehending what was said. Shrunken iris, mouth half open... I personally think the reaction makes sense.
If you are a penis owner and piss from the standing position, you can arc the stream just so down the smooth porcelain interior of the toilet bowl, letting the piss flow neatly into the water making nary a sound
