It makes set open into dance (3-4)
I believe the answer is:
one-step
'dance' is the definition.
(I know that one-step is a type of dance)
'it makes set open' is the wordplay.
'it makes' indicates an anagram.
'set'+'open'='setopen'
'setopen' anagrammed gives 'ONE-STEP'.
'into' acts as a link.
(Other definitions for one-step that I've seen before include "(Very short?) ballroom dance" , "Vigorous dance" , "Style of foxtrot" , "Foxtrot's precursor" , "Kind of foxtrot" .)