Head hosting English gathering without taking sides (9)
I believe the answer is:
neutrally
'without taking sides' is the definition.
(I've seen this before)
'head hosting english gathering' is the wordplay.
'head' becomes 'nut' (informal term for somebody's head).
'hosting' indicates putting letters inside (inserted letters are welcomed in or hosted).
'english' becomes 'E' (abbreviation).
'gathering' becomes 'rally' (rally is a kind of gathering).
'nut' enclosing 'e' is 'neut'.
'neut'+'rally'='NEUTRALLY'
(Other definitions for neutrally that I've seen before include "Without taking sides" , "In an inoffensive way" , "Impartially" , "Displaying no bias" .)