A surge in activity catches learner out (6)
I believe the answer is:
abloom
'out' is the definition.
(I've seen this before)
'a surge in activity catches learner' is the wordplay.
'surge in activity' becomes 'boom' (I am not sure about this - if you are sure you should believe this answer much more).
'catches' indicates putting letters inside.
'learner' becomes 'l' (as in a learner driver with L-plates on their car).
'boom' placed around 'l' is 'bloom'.
'a'+'bloom'='ABLOOM'
Can you help me to learn more?
(Other definitions for abloom that I've seen before include "Flowering" , "In flower" , "covered in flowers?" , "full of colour" , "Flourishing" .)