Nouns ending in -sion are feminine.
The suffix forms abstract nouns of action or state.
Is répression masculine or feminine?
larépression
The rule behind it
100% of -sion nouns are feminine
In context
Le germe de la révolution est la répression.
The seed of revolution is repression.
En guise de répression, le gouvernement expulse les étrangers en situation irrégulière.
The government is expelling illegal aliens as part of a crackdown.
Les citoyens vivaient dans une peur constante de dénonciations et de répression.
Citizens lived in constant fear of denunciation and repression.