Current appearance by second side impressing manager finally (9)
I believe the answer is:
airstream
'current' is the definition.
(I've seen this before)
'appearance by second side impressing manager finally' is the wordplay.
'appearance' becomes 'air' (I've seen this before).
'by second side' becomes 'steam' (I can't justify this - if you can you should give a lot more credence to this answer).
'impressing' indicates putting letters inside (impress historically meant to conscript).
'finally' indicates one should take the final letters.
The final letter of 'manager' is 'r'.
'steam' going around 'r' is 'stream'.
'air'+'stream'='AIRSTREAM'
Can you help me to learn more?
(Other definitions for airstream that I've seen before include "Atmospheric current" , "What might waft" , "Jet" , "wash" , "Atmospheric flow" .)