Attendant initially sweeping away (6)
I believe the answer is:
abroad
'away' is the definition.
(I've seen this before)
'attendant initially sweeping' is the wordplay.
'initially' says to take the initial letters.
'sweeping' becomes 'broad' (similar in meaning).
The initial letter of 'attendant' is 'a'.
'a'+'broad'='ABROAD'
(Other definitions for abroad that I've seen before include "At large - overseas" , "In foreign land" , "Overseas; (of rumour) widely current" , "In another country, not at home" , "Out of doors - in foreign parts" .)