Far-fetched but kind of square and everything (4)
I believe the answer is:
tall
'far-fetched' is the definition.
(I've seen this in another clue)
'kind of square and everything' is the wordplay.
'kind of square' becomes 'T' (a T-Square is a technical drawing instrument).
'and' is a charade indicator (letters next to each other).
'everything' becomes 'all' (all things).
't'+'all'='TALL'
'but' acts as a link.
(Other definitions for tall that I've seen before include "High in stature" , "Of great stature" , "description of a giraffe?" , "Lofty; unlikely" , "Like giants" .)