What does the phrase "wink and nod" or "wink-and-nod" mean in the following sentences?: *So no litmus test on abortion -- except the protection of “women’s rights,” which everyone in the room understood as a reference to abortion. Obama’s pose of neutrality came with a theatrical wink and nod. Everyone got the joke. *The original status of forces agreement, negotiated in the last days of the Bush administration, called for the withdrawal of all American troops by the end of 2011. But the agreement was reached with a wink-and-nod understanding that a politically palatable way would be found to keep a substantial American troop presence in the country after that date.