Time to arrange sea duty (7)
I believe the answer is:
tuesday
'time' is the definition.
The definition and answer can be both related to time as well as being singular nouns.
Perhaps you can see a link between them that I can't see?
'arrange sea duty' is the wordplay.
'arrange' indicates anagramming the letters.
'sea'+'duty'='seaduty'
'seaduty' anagrammed gives 'TUESDAY'.
'to' acts as a link.
Can you help me to learn more?
(Other definitions for tuesday that I've seen before include "Day for sea duty?" , "24-hour period" , "Is it suet day?" , "forty eight hours before Chesterton's man" , "early in the week" .)