I think it would be ‘ass’ or ‘butt’.
Hey who said I’m not British
I’ve only been living here in the few years and am still coming across language differences, usually when someone stares blankly at you (hire car vs rental car, cilantro vs coriander, are some of the more recent ones).
But I’ve never come across those particular technical words in that context (cute as in sexy I guess has an american ring to it)… None of links you gave really showed an anything to with their American vs English conetations (I realize they may first have been used in the states, but that doesn’t mean the rest of world uses a different word,) The term Autism was coined by a Swiss guy. And I’ve not heard of anyone talk about a fusion warhead and as anything other than a Hydrogen bomb, either here or back home.
I think Chronos has the right of it " the asterices just indicate words of American origin, without regards to where they’re used." Given their development in the States, Hydrogen Bomb, and Neutron Bomb were probably coined in America but if “Autism” was coined by a Swiss I’ve no idea how that got in. All three are technical terms and - I assume - mean the same both sides of the pond.
No evidence but I suspect “cute” has come into British English from American imports - films, tv, etc. Use of cute outside of the fluffy kitten area (and possibly the attractive but not aggressively sexy girl useage) sounds very American to me. I’ve still not got over hearing two middle aged American ladies describe the Leonardo drawing of “The Virgin and Child with St Ann and St John the Baptist” in the National Gallery as “cute” - it is not a word I can imagine a Brit using about an old masterpiece, whatever the subject.
Well, the spelling is a bit of a different matter. And ‘bottom’ would be understood. Pavement and pants would be bewildering, because they both have alternate meanings in US speak.
True, if you were British, you’d talk out of your arse 
There is no “arse” in American English. It’s “ass” in adult language. But the equivalent of “bottom” would probably be “butt” or “rear end.”
Or “behind”, in some contexts.
The hydrogen bomb and atom bomb are different. Atom bomb is a fission a hydrogen bomb is a fusion device. Growing up in Los Alamos may have made me more sensitive to the difference but I don’t remember anyone referring to fission devices as hydrogen bombs or fusion devices as atom or atomic bombs.
I think this calls for a clarification.
Terms I’ve heard used for fusion weapons:
- Hydrogen bomb/nuke
- H-bomb
- Fusion bomb/nuke
- Thermonuclear bomb/nuke
Terms I’ve heard used for fission weapons:
-
Fission bomb
-
Atom bomb
-
Atomic bomb
-
A-bomb
Terms I’ve heard used for neutron weapons: -
Enhanced radiation weapon
-
Neutron bomb
Now which ones of these are in use in Britain? I presume all, are there any others?
I’ve also occasionally heard the rather apt “Hellbomb”. I’m not sure why it never caught on.
You mid-atlantic dandy. Wear your grey y-fronts with pride, boy!
I thought you guys called them nuke-you-lar now?

‘Homely’, on the other hand, has drastically different meanings. As does ‘suspenders’.
“I’m King Kong
Got a hydrogen bomb,
I can blow up your houses
So you’d better beware!”
–Some Britsih guys. 1968
Seems like at least some Brits were familiar enough with this one almost 40 years ago to incorporate into a regional ballad.
Another vote that * = origin/coinage
Care to elaborate? Over here, “homely” is a somewhat more polite way to say “ugly”, though I suppose I can see how it could mean “like a home”. But I’ve never heard “suspenders” for anything other than “strips of cloth which go over the shoulders and clip onto trousers to hold them up”.
If somebody’s house was warm and welcoming, you could describe it as homely. Braces are what old mean use to hold their trousers up - suspenders are for stockings.