Ballet posture of Lincoln in square dance (9)
I believe the answer is:
arabesque
'ballet posture' is the definition.
(I've seen this before)
'lincoln in square dance' is the wordplay.
'lincoln' becomes 'abe'.
'in' indicates putting letters inside.
'dance' is an anagram indicator.
'square' is an anagram of 'arsque'.
'abe' inserted into 'arsque' is 'ARABESQUE'.
'of' is the link.
(Other definitions for arabesque that I've seen before include "A square be a ballet movement?" , "Ballet position with one leg raised" , "Intertwined ornamental design" , "Decorative design; ballet pose" , "part of ballet" .)