Not really at all queer, I figure that's the same on all sides (11)
I believe the answer is:
equilateral
'figure that's the same on all sides' is the definition.
(shape with all sides the same length)
'not really at all queer i' is the wordplay.
'not really' is an anagram indicator (the letters not in their usual or \'real\' order).
'at'+'all'+'queer'+'i'='atallqueeri'
'atallqueeri' is an anagram of 'EQUILATERAL'.
(Other definitions for equilateral that I've seen before include "keeping the sides the same" , "Having all sides of equal length" , "(Of a triangle) having sides the same" , "Like regular shapes" , "square, perhaps" .)