Interesting variation. After reading this post, I began wondering if English had anything similar. Some people do shorten "dinner" to "din-din," but it is considered to be a child's word for dinner. That said, I've rarely heard a child actually use it. It seems to me to be more of something an adult would say when using "baby talk" or when adults are attempting to make language lighter/fun/more playful.
Then again, dinner is not a compound as it is in Turkish, so I began to wonder if English speakers ever did anything similar with compound words and realized that we do. So, I made a list with some examples. The following list might be more helpful to Turkish speakers learning English, but English speakers might find it interesting, too. The word on the left will be the full compound word and the word bolded in parentheses will be the truncated version of it. Keep in mind that most English compound words need to be used in their complete form. The list of those that are often truncated is as follows:
I would suspect there are other examples as well. Also, some of these truncated versions are more common replacements for the full compound than others. For example, copy for photocopy is very common to the point that you rarely hear photocopy used anymore. On the other hand, print for fingerprint is certainly not as common of a replacement as copy for photocopy.
I don't have any stats to back up my experiences as an English speaker and a very cursory search for trends such as these did not yield anything, but that doesn't mean they don't exist.
Also, for the most part, such truncations of the full compound word, as far as I know, are pretty common throughout the United States. In other words, such usage is not regional. I do wonder if akşam for "akşam yemeği" might be a regional colloquialism. Do any native Turkish speakers have any opinions on this? Also, I'd be interested in knowing which compound words or phrases in Turkish have been similarly shortened. Do any native Turkish speakers have any examples of this?