A person or should I rather say a dick who likes to reminisce about every little thing and somehow tie it into their present life. The smallest things takes them back to a time and their so annoying about it, they become a nostalgic+dick=.....
Mike: Omg, Jenny!
Mike: This glass of Orange Juice reminds me of the OJ Simpson trial...
Jenny: Stop being a nostaldick!
When a person is feeling nostalgic about a previous sexual partner. And has sex with them to reminisce.
"Hey man, I ended up sleeping with Joan again."
"I guess, I was feeling Nostaldick!"