Lookups on Merriam-Webster.com spiked on May 2, 2011.
Osama Bin Laden's death prompted discussions about whether some people would consider him a martyr.
For example, as one journalist wrote, "From the perspective of most peace-loving Westerners, a despicable human being has been eliminated and justice has been served. To many radicalized Muslims, the Navy SEALs have created another martyr." (John Cassidy, The New Yorker online, May 3, 2011)
Martyr means "a person who is killed or suffers greatly for a religion or cause."
It comes from the Greek word for "witness," the term used for early Christians who were put to death because they would not renounce their faith. (In the book of Acts, Jesus refers to his followers as "witnesses.")