Heißhunger·A sudden appetite for something specific, often something sweet (literally means hot hunger).
Mahnmal·A specialised form of memorial, which would be Denkmal. mahnen means to remind, caution, urge, Mal is the -ial part. Hence why Holocaust memorial is a very, very fuzzy translation.
Kuckuckskind·(noun) Literally cuckoo's child: A child who is not raised by their biological father, but is raised by another man who (wrongly) assumes he is the biological father.
Kopfkino·Lit. 'mind-cinema'. The unvoluntary thoughts of usually bad, disgusting or scary things or situation caused by hearing them mentioned or talked about.
Aufhänger·An idea or event that gets a discussion or conversation started (both in a journalistic and casual context).