Venskabsby/sister city/twin town

From Gyldendal's big Danish-English dictionary:

venskabsby sb adopted town, twin town
-er (også)paired towns, twinned towns, twin towns; være ~ med be twinned with.

Once again, this should be marked as UK English. Twin town just sounds plain silly in American English. There are twin cities (Minneapolis/St. Paul for example), but twin towns? The entry should have included the North American term: sister city.

Google hits:
twin town - 254,000
sister city - 835,000

It drives me crazy that they don't include the term that is actually way more common! I'm not saying "take the UK" terms out. I'm saying, mark them as being what they are: unintelligible to the majority of US English speakers. And include the US term. Please!

følgebrev/cover letter/covering letter

From Gyldendal's big Dansk-Engelsk dictionary:

følgebrev covering letter; (advisseddel) letter of advise, delivery letter.

I've never heard it called a "covering letter." I've only ever heard it called a "cover letter."
And, indeed, if we take a look at the number of Google hits each version receives:
covering letter = 1,120,000
cover letter = 7,190,000
You will see that the form I'm familiar with is about seven times as common. Why does Gyldendal not include it?

As it happens I don't really accept "letter of advise" or "delivery letter" as proper English either. "Letter of advise" should be spelled "advice" (as it is under the Gyldendal's entry for "advisbrev." I'm not sure how either of these should be translated into English. Honestly, I bought the dictionary so I wouldn't have to figure things like this out...

ovenlys/roof light/skylight

Finally, a word from a Danish dictionary. And not just any Danish dictionary, but Gyldendal's enormous Dansk-Engelsk Ordbog, the Vinterberg & Bodelsen behemoth.

ovenlys et overhead light; (i tag) roof light.

I've never heard of a "roof light." So I did an image search on Google and guess what? Apparently "ovenlys" should be translated as "skylight" in U.S. English. And sure enough, if you do a Google image search for "roof light" you get a bunch of hits for British pages showing skylights and also a bunch of pages for the lights that go on top of police and taxi cab roofs.

Google hits:
roof light 155,000
skylight 6,040,000

So, my point once again, is that the UK term should be marked as such since it is essentially unintelligible in US English and the dictionary should provide the (overwhelmingly more widespread) US term: skylight.

apoteker/dispensing chemist/pharmacist

drogerihandler subst; slightly old-fashioned (=apoteker) dispensing chemist; US: druggist.

OK, again the American in me has to say, what the heck? This is from Kirkeby's Stor Norsk-Engelsk Ordbok. What gets me is that they give a specific American translation, but they give "druggist." I found the term "druggist" in Merriam Webster, but I have to say this is pretty much the only place I've ever heard it. The everyday American term is "pharmacist." Why doesn't Kirkeby include the translation "pharmacist"? And why does Kirkeby mark "druggist" as the US term?

A quick Google search really says it all:
dispensing chemist: 46,300 hits
druggist: 784,000 hits
pharmacist: 18,400,000 hits

I just don't understand why my Norwegian to English dictionaries so frequently don't include the most normal, most common translation for these terms. Seriously. Eighteen million hits is a lot of hits.