Overly formal to enquire about manned orbiter (6)
I believe the answer is:
prissy
'manned orbiter' is the definition.
I can't tell whether this defines the answer.
'overly formal to enquire about' is the wordplay.
'overly formal' becomes 'iss' (I can't explain this - if you can you should believe this answer much more).
'to enquire' becomes 'pry' (prying is a kind of enquiring).
'about' is an insertion indicator.
'iss' going within 'pry' is 'PRISSY'.
Can you help me to learn more?
(Other definitions for prissy that I've seen before include "Strait-laced" , "Fussily respectable" , "Fussy and prudish" , "Prudishly fussy" , "Exaggeratedly proper" .)