St. Stephen is remembered as the first martyr of the church. The name Stephanos in Greek means "crown" or "wreath", as in a victorious athlete's laurel wreath. I don't know whether the saint lived up to the name he already had, or is honored as having attained the crown of martyrdom.
Catechism of the Catholic Church, §2473The trial, witness, and death of Stephen are described in the New Testament book of Acts, chapters 6 and 7. In spite of some of the simpering iconography, he must have been a man of great physical courage in addition to great faith. I hope I don't have to find out what it would be like to face death by stoning.
Martyrdom is the supreme witness given to the truth of the faith: it means bearing witness even unto death. The martyr bears witness to Christ who died and rose, to whom he is united by charity. He bears witness to the truth of the faith and of Christian doctrine. He endures death through an act of fortitude. "Let me become the food of the beasts, through whom it will be given me to reach God."
[St. Ignatius of Antioch, Ad Rom. 4,1:SCh 10,110]
"Behold, I see the heavens opened, and the Son of Man standing at the right hand of God."
[Acts 7:56, ESV]