A picture of Ashling Murphy in her graduation robes was projected on a Trinity College building as landmarks across the country were lit up to mark St Brigid's Day 2022.
The event, organised by the group Herstory, is a celebration of women who have contributed to Irish society and culture.
In poignant scenes at Trinity College on Monday night, a minute's silence was observed for Ashling Murphy, the primary school teacher who was killed last month
A man has appeared in Tullamore District Court charged with Ashling's murder.
From next year St Brigid's Day, which falls on February 1, will be a public holiday, the first to be named after a woman.
The day marks the beginning of spring and the Celtic festival of Imbolc.
The event kicked off on Monday evening, when hundreds of people gathered to mark the launch at Trinity College in Dublin.
Meanwhile, the GAA has called for its male members to "listen and learn" in the wake of Ashling Murphy's murder.
Writing in the GAA monthly club newsletter, the GAA's Community and Health manager Colin Regan paid tribute to the teacher and member of Kilcormac-Kiloughey camogie club, saying: "Ashling epitomised the values we seek to bring to life. She loved the game she played, and she played the game with love.
"As men, we need to take a good look at ourselves, our attitudes, biases, and behaviours. We also need to look inwardly as an Association.
"We need to welcome constructive criticism and we need to see this watershed moment as an opportunity. Only then can we start to co-design some of the solutions.
"Women are working shoulder to shoulder in clubs with men who share their vision. Men who recognise that a truly healthy club and association is one where male and female qualities compliment each other and become more than the sum of their parts.
"We need to engage these men and urge them to be the agents for positive change in every aspect of their lives. Including when they are on a Whatsapp group and inappropriate or degrading content or comments are made about women."
