cat ‧ a ‧ lyst /ˈkætl-əst, ˈkætl-ɪst/ BrE AmE noun [countable]
[ Date: 1900-2000 ; Origin: catalysis , on the model of analyst ]
1 . technical a substance that makes a chemical reaction happen more quickly without being changed itself
2 . something or someone that causes an important change or event to happen
catalyst for
They hope his election will act as a catalyst for reform.
—catalytic /ˌkætlˈɪtɪk◂/ adjective