forfended

The likelihood of suffering from PTSD is cumulative, meaning that if PTSD could be measured so effectively, and thus forfended a soldier who spends a year and a half in Iraq but comes within a tenth of getting full-blown PTSD will still be 90% of the way to PTSD when they return a year later.

On the Scene at the Iraq Hearings - The Caucus Blog - NYTimes.com 2008

Then he called Sir Bors, Sir Ector de Maris, and Sir Lionel, and told them how the queen had forfended him the court, and so he was in will to depart into his own country.

Le Morte d'Arthur: Sir Thomas Malory's book of King Arthur and of his noble knights of the Round table 2003

Then he called Sir Bors, Sir Ector de Maris, and Sir Lionel, and told them how the queen had forfended him the court, and so he was in will to depart into his own country.

Le Morte Darthur: Sir Thomas Malory's Book of King Arthur and of his Noble Knights of the Round Table, Volume 2 1470