Learner in station holder (5)
I believe the answer is:
clamp
'holder' is the definition.
The answer and definition can be both man-made objects as well as being singular nouns.
Perhaps they are linked in a way I don't understand?
'learner in station' is the wordplay.
'learner' becomes 'l' (as in a learner driver with L-plates on their car).
'in' is an insertion indicator.
'station' becomes 'camp' (I can't explain this - if you can you should give a lot more credence to this answer).
'l' put within 'camp' is 'CLAMP'.
Can you help me to learn more?
(Other definitions for clamp that I've seen before include "bracket" , "Gripping tool" , "squeeze" , "Strong fastener" , "Fix firmly" .)