Explains away ultimately puzzling disappearances (7)
I believe the answer is:
glosses
This could be a double definition.
'explains' is the first definition.
The answer and definition can be both to do with communicating as well as being verbs in their -s form.
Maybe there's an association between them I don't understand?
'away ultimately puzzling disappearances' is the second definition.
Although both the answer and definition are plural nouns, I don't see how one could define the other.
Can you help me to learn more?
(Other definitions for glosses that I've seen before include "Provides explanation" , "Gives lustre to" .)