Worry about sailors recruiting in times past (7)
I believe the answer is:
concern
'worry' is the definition.
(I know that worry can be written as concern)
'about sailors recruiting in times past' is the wordplay.
'about' becomes 'c' (circa).
'sailors' becomes 'RN' (abbreviation for Royal Navy).
'recruiting' is an insertion indicator (inserted letters are recruited into the word).
'in times past' becomes 'once' (I've seen this before).
'c'+'rn'='crn'
'crn' placed around 'once' is 'CONCERN'.
(Other definitions for concern that I've seen before include "Cause of anxiety" , "Firm - interest" , "Business organisation" , "Affect; solicitude" , "Business - worry" .)