A question about the definition of a word in a dictionary

Hi, folks!

The following is the definition of cystic fibrosis given in the Collins Cobuild English Dictionay for Advanced Learners:

“Cystic fibrosis is a serious disease of the glands which usually affects children and can make breathing difficult.”

To native-speaker English pundits it may be a matter of common sense that the relative pronoun clause stating with “which” refers to “disease.” But to an ELS student like me the clause appears to refer to “glands.” Grammatically, simply because the clause follows “glands,” doesn’t it refer to “glands”? Or am I dead wrong?

Geoff_One, Guest, Travis, Uriel, what do you guys think?

If I’m right, how would you guys rewrite the definition to make it more lucid?

No. "Which" refers to "disease."

Imagine taking out "of the glands" and it would read "“Cystic fibrosis is a serious disease WHICH usually affects children and can make breathing difficult.”

Adam, are you saying that the which clause can never grammatically refer to "glands"?

No, Adam is right (mark it on your calendar!): The word "disease" is the subject here; "of the glands" is simply being used as a descriptor of "disease".

You can have diseases of the glands, diseases of the heart, diseases of the eye, the brain, the skin, whatever; it is semantically the same as saying "glandular disease", "heart disease", etc. "Of the ____" is essentially being used as if it were an adjective.

Therefore, "which" is referring back to "disease", not to the description of the disease.

Does that make more sense, or have I confused you more?

Adam & Uriel,

I'm still a bit confused. English grammar is very complex. I doubt if I can master it in my life time.

If a comma was placed between "glands" and "which," then would the "which " clause refer directly to "cystic fibrosis" or still refer to "desease"? Or would such a use of a comma make any difference in this case?

Please let me know.

Thank you for your help, guys.