Echo in club creates rhythm (4)
I believe the answer is:
beat
'rhythm' is the definition.
(synonyms)
'echo in club' is the wordplay.
'echo' becomes 'e' (phonetic alphabet: alpha, bravo, charlie etc.).
'in' means one lot of letters goes inside another.
'club' becomes 'bat' (as in sporting equipment).
'e' inserted into 'bat' is 'BEAT'.
'creates' acts as a link.
(Other definitions for beat that I've seen before include "Thrash with rhythm?" , "Defeat; pulsate" , "Conquer" , "Rhythm, stir vigorously" , "Rhythmic musical unit" .)