Lonesome Indian, somehow lacking depth (3-11)
I believe the answer is:
one-dimensional
'lacking depth' is the definition.
(I've seen this before)
'lonesome indian somehow' is the wordplay.
'somehow' indicates an anagram.
'lonesome'+'indian'='lonesomeindian'
'lonesomeindian' anagrammed gives 'ONE-DIMENSIONAL'.
(Other definitions for one-dimensional that I've seen before include "Unsophisticated" , "Superficial" , "Lacking in depth" .)