Valid (adjective) — صحيح ومقبول: Legally binding; also logically sound or well founded. Below are 7 words with a similar meaning; the linked ones have full GL Dictionary entries with their meaning in Arabic.
Allowed by law; genuine and reasonable.
Obligatory and enforceable — a promise or rule that holds; also the spine and cover that hold a book's pages together
Approved by authority; a person holding office.
soundlawfulwell foundedreasonable
Able to be shown to be right or reasonable.
In accordance with fact; genuine; loyal.