/seyf-tee mar-jin/ – Phrase
Definition: Khoảng cách an toàn hoặc dự phòng để đảm bảo an toàn
A more thorough explanation: time, space, or other variables (=things that can change) allowed for something to be safe (=with no risk of harm or danger)
Example: The inquiry found that the plane did not have sufficient fuel to land with enough of a safety margin.