add. ·- open or free admission to all; hospitable welcome; free opportunity.
2. open door ·add. ·- in modern diplomacy, opportunity for political and commercial intercourse open to all upon equal terms, ·esp. with reference to a nation whose policy is wholly or partially fixed by nations foreign to itself, or to territory newly acquired by a conquering nation. in this sense, often used adjectively, as, open-door system, open-door policy, ·etc.