Oxford Dictionary English security deposit nounnoun BrE BrE//sɪˈkjʊərəti dɪpɒzɪt// ; NAmE NAmE//səˈkjʊrəti dɪpɑːzɪt// [usually singular] (especially North American English) Add to my wordlistjump to other resultsa 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.See security deposit in the Oxford Advanced American DictionaryCheck pronunciation: security deposit oxfordlearnersdictionaries.com