There is no 8-letter word, but there are several 7-letter words:agnaticanticarcartingcratinggranitatracing
defaced
Saguaro
spiders
Respite
aneroid
Isolate.
libertyquietlyquilterrebuilttumbler
Breeder is a 7 letter words using only those letters
There is no 7-letter word using those letters, but there are two 6-letter options:confabforbad
There is no 7-letter word available with those letters, the longest words are these 6-letter words:garveygreaveraggeeregavereggae
There is no 8-letter word, but there are several 7-letter words:agnaticanticarcartingcratinggranitatracing
The 7 letter words are address, dwarves, and swarmed.
There are three 7-letter words possible:roosterrooterstoreros
Hipster
Endmost.
Respite.