un ‧ seat /ʌnˈsiːt/ BrE AmE verb [transitive]
[ Word Family: noun : ↑ seat , ↑ seating ; verb : ↑ seat ≠ ↑ unseat ; adjective : ↑ seated ]
1 . to remove someone from a powerful job or position:
an attempt to unseat the party leader
2 . if a horse unseats someone, it throws them off its back