antipassback means A security mechanism preventing an access card or similar device from being used to enter an area a second time without first leaving it (so that the card cannot be passed back to a second person who wants to enter). Lexicurio rates it Rare gem — a strength score of 83 out of 100.
Etymology
From anti- + passback.
noun
- A security mechanism preventing an access card or similar device from being used to enter an area a second time without first leaving it (so that the card cannot be passed back to a second person who wants to enter).