Other forms: curtailments
A curtailment is an ending or restriction. The curtailment of your allowance means you'll have to get a job if you want to keep buying new video games.
The noun curtailment is a somewhat formal way to say "limitation." It comes from the Old French court, "short," and a root meaning "to cut." You can think of a curtailment as cutting something short, whether it's the curtailment of your bike riding once the temperature drops in the fall, or the curtailment of your driving privileges after you get into a fender-bender.