[rule of the road] (1871): a customary practice (as driving always on a particular side of the road or yielding the right of way) developed in the interest of safety and often subsequently reinforced by law; esp: any of the rules making up a code governing ships in matters relating to mutual safety
RULE OF THE ROAD
Meaning of RULE OF THE ROAD in English
Merriam-Webster English vocab. Английский словарь Merriam Webster. 2012