Don't forget to pick it up again (9)
I believe the answer is:
recollect
'don't' is the definition.
Both the definition and answer are verbs in their base form.
Perhaps they are linked in a way I don't understand?
'forget to pick it up again' is the wordplay.
I cannot really see how this works, but
'it' could be 't' (abbreviation. e.g. in 'tis) and 't' is located in the answer.
'again' could be 're' (prefix meaning 'again') and 're' is present in the answer.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for recollect that I've seen before include "Call to mind" , "Look back on" , "Bring back to mind." , "Recall to mind" , "Remember" .)