This is the 518th most frequent Persian word.
سابق
Former; previous.
Here, 'سابق' refers to a person's previous official position.
او رئیسجمهور سابق کشور است.
He is the former president of the country.
In this sentence, 'سابق' indicates a situation that was true in the past.
این کتاب سابق در کتابخانه موجود بود.
This book was previously available in the library.
Here, 'سابق' signifies a relationship that existed in the past and is no longer the case.