Still something confusing me about compoud names:
One of meanings of the phrase [top hat rack] is [the highest hat rack], now:1-we can get the meaning easily here so this is not the problem 2-this same phrase constitute a compound name also this is not the problem 3- now to know that the compound name has the same meaning of the phrase here comes my confusion, is the word became compound just because someone liked to make it compound even though the same meaning existed with no compounding and so he made new compound from it by changing the way we pronounce it as phrase and with making new entry for that compound in dictionary? why that someone chose to make it compound and did not choose to make compound of other phrases like [top banana tree]?
5 Answers
In linguistics, a compound is a lexeme (less precisely, a word) that consists of more than one stem. Compounding or composition is the word formation that creates compound lexemes (the other word-formation process being derivation). Compounding or Word-compounding refers to the faculty and device of language to form new words by combining or putting together old words. In other words, compound, compounding or word-compounding occurs when a person attaches two or more words together to make them one word. The meanings of the words interrelate in such a way that a new meaning comes out which is very different from the meanings of the words in isolation.
If someone decides or chooses at a certain point to make a compound word and not another (hat for banana), you should ask that person in particular. Maybe he was familiar about hats and not about bananas. But I think it´s not an individual choice.It comes out of a linguistic situation and its social context.
For instance, you can ask Ringo Starr why did he coin ´a hard day´s night´ expression. But he said that in 1965/66 when he was living a very specific situation and he´d probably had no idea how to ´choose´ that expression today.
Also, I think it is a rack for top hats (a special kind of hat) as opposed to the highest hat rack.
::: I realize the thread is old, too, guys :::
Is it being used to make a distinction? For example if there were three racks in a hat shop, and the other two had fedoras and stetsons then the other one would probably be designated as the "top hat rack."
Do I believe this? Not really. 
To take it further, there are three hat racks one beneath the other. The "top hat rack could be the highest one. This is getting crazy.
ciao 
The people who decide what to put in dictionaries make their decisions based on how people talk, not their own whims. I never heard the phrase top hat rack and I wonder where it came from. There are three forms of compound words
the closed form, such as baseball, redhead, keyboard, notebook;
the hyphenated form, such as daughter-in-law, six-pack, six-year-old;
and the open form, such as day trip, post office, half sister.
I would agree that it's easy to find questionable, or equivocal, information about language and grammar. Be sure to evaluate the source of information you find.
I don't know what you mean by compound words.
