I am to have place for duty (10)
I believe the answer is:
imposition
'for duty' is the definition.
(thesaurus)
'i am to have place' is the wordplay.
'i am' becomes 'I'm' (contraction).
'to have' says to put letters next to each other.
'place' becomes 'position' (positioning is a kind of placing).
'im'+'position'='IMPOSITION'
(Other definitions for imposition that I've seen before include "Unwelcome demand or burden" , "tax" .)