Chairman maintains church is centre of harmful masculinity (8)
I believe the answer is:
machismo
'masculinity' is the definition.
(machismo is a kind of masculinity)
'chairman maintains church is centre of harmful' is the wordplay.
'chairman' becomes 'Mao' (Chinese leader Chairman Mao).
'maintains' indicates putting letters inside.
'church' becomes 'ch' (abbreviation on maps etc).
'centre of' says to take the centre.
The middle letter of 'harmful' is 'm'.
'ch'+'is'+'m'='chism'
'mao' going around 'chism' is 'MACHISMO'.
(Other definitions for machismo that I've seen before include "Hi, commas, strangely, might have exaggerated masculinity" , "Exaggerated masculine pride" , "virile obsession" , "form of pride" , "Expression of male pride" .)