Plan to get a hundred deer (5)
I believe the answer is:
chart
'plan' is the definition.
(I know that chart is a more specific form of the action plan)
'get a hundred deer' is the wordplay.
'get' is a charade indicator (letters next to each other).
'a hundred' becomes 'C' (Roman numeral).
'deer' becomes 'hart' (hart is a kind of deer).
'c' put next to 'hart' is 'CHART'.
'to' acts as a link.
(Other definitions for chart that I've seen before include "series of plots?" , "Table or graph" , "Table or diagram" , "what could be a pie" , "Hit parade" .)