Using all the letters you get: saguaro
outside
chrisms
You can make one seven lettered word from these letters which is nirvana.
cabbage, baggage
Olympic
outside
You can make two 7 letter words : COSTARS and CASTORS
chrisms
laminae
Wiriest
netball
choanae
stammer
Demented
lidless
Germany
No 7 letter words, the longest is 6 letters, purist