Eccentric when out and about (5)
I believe the answer is:
'eccentric' is the definition.
(I know that eccentric can be written as outre)
'out and about' is the wordplay.
'and' means one lot of letters go next to another.
'about' becomes 're' (regarding).
'when' acts as a link.
(Other definitions for outre that I've seen before include "Eccentric or unseemly - in France" , "Somewhat unusual" , "flaky" , "Exotic" , "Weird" .)