cur ‧ tail /kɜːˈteɪl $ kɜːr-/ BrE AmE verb [transitive] formal
[ Date: 1400-1500 ; Origin: curtal 'to cut short an animal's tail' (15-17 centuries) , from Old French courtault 'animal with a shortened tail' ; influenced by tail ]
to reduce or limit something SYN cut :
The new law will curtail police powers.
severely/drastically curtail
Budget cuts have drastically curtailed training programs.
—curtailment noun [uncountable and countable]