From here one observes bachelor flat (5)
I believe the answer is:
blimp
'from here one observes' is the definition.
Although both the answer and definition are singular nouns, I can't see how they can define each other.
'bachelor flat' is the wordplay.
'bachelor' becomes 'B' (abbreviation e.g. BA=Bachelor of Arts).
'flat' becomes 'limp' (I can't justify this - if you can you should believe this answer much more).
'b'+'limp'='BLIMP'
Can you help me to learn more?
(Other definitions for blimp that I've seen before include "full of hot air?" , "Small nonrigid airship" , "Large inflatable" , "Elderly pompous reactionary person" , "David Low's cartoon colonel - airship used for publicity" .)