1. a circle of flowers or leaves worn on the head
2. an arrangement of flowers and leaves, especially in the shape of a circle, placed on graves, etc. as a sign of respect for somebody who has died

Link to present incidents:
Chancellor Angela Merkel and President Joachim Gauck were among those who took part in a rally organized by Muslim groups near Berlin's iconic Brandenburg Gate and the French embassy, where wreaths were laid for the 17 people killed by Islamic extremists in Paris last week.