security deposit
noun /sɪˈkjʊərəti dɪpɒzɪt/
/sɪˈkjʊrəti dɪpɑːzɪt/
[usually singular] (especially North American English)- a sum of money you pay when you rent a place to live and that is returned when you leave if you do not cause any damage
- The landlord requires a security deposit of one month's rent.