Honoured with a nosh up - though a tin opener is involved (5)
I believe the answer is:
feted
'honoured with a nosh up' is the definition.
I can't tell whether this definition defines the answer.
'though a tin opener is involved' is the wordplay.
'though' becomes 'feed' (I can't justify this - if you can you should believe this answer much more).
'opener' indicates taking the first letters.
'is involved' is an insertion indicator.
The first letter of 'tin' is 't'.
'feed' enclosing 't' is 'FETED'.
Can you help me to learn more?
(Other definitions for feted that I've seen before include "Wined and dined, celebrated" , "Honoured with festivities" , "Wined, dined and honoured" , "Lionised" , "Honoured lavishly" .)