Definitely not nuts, initially supporting Wanderers (6)
I believe the answer is:
nomads
'wanderers' is the definition.
(nomad is a kind of wanderer)
'definitely not nuts initially supporting' is the wordplay.
'definitely not' becomes 'no'.
'nuts' becomes 'mad' (I've seen this in other clues**).
'initially' indicates taking the first letters.
The initial letter of 'supporting' is 's'.
'no'+'mad'+'s'='NOMADS'
(Other definitions for nomads that I've seen before include "People who move about according to the seasons" , "Gypsies" , "Vagrant peoples" , "They travel from place to place with no permanent home" , "Damson for wandering tribes" .)