Elizabeth Jane Weir (born February 20, 1948) is a lawyer and politician in New Brunswick, Canada. She was elected leader of the New Democratic Party of New Brunswick in 1988 and became an opposition voice to the Liberal government, which held all 58 seats in the Legislative Assembly of New Brunswick.

Born in Belfast, Northern Ireland, Weir was educated at the University of Waterloo and the University of Western Ontario. She has taught at York University and the University of New Brunswick. Weir was first elected to the legislature in 1991 in the riding of Saint John South where she defeated the liberal John Mooney by only 78 votes . In 1995, the riding became Saint John Harbour and she was re-elected in 1995, 1999 and 2003. During that time, she was the sole New Democrat in the legislature.

At the 2003 federal NDP convention at which Jack Layton would be elected party leader, Weir sought the presidency of the federal party against re-offering incumbent Adam Giambrone. Midway through the convention, Giambrone and Weir decided to seek a co-presidency. Many delegates balked, especially at the assumption that they could push through a sudden constitutional change in a party often dearly concerned with internal process. The joint ticket was withdrawn, and Weir placed second after Giambrone and before a challenger from the NDP Socialist Caucus.

Dr. Elizabeth Weir is a fictional character in the Canadian-American Sci-Fi Channel television series Stargate Atlantis, a military science fiction show about a military team exploring another galaxy via a network of alien transportation devices. Elizabeth Weir is introduced as a recurring character in the Stargate SG-1 season seven two-parter, "Lost City". She does not hold any military rank since she is a civilian. Weir is the leader of the Atlantis expedition in Stargate Atlantis until the last episode of season three, titled "First Strike".

The character was primarily played by Torri Higginson, although when introduced in the Stargate SG-1 two-parter "Lost City", she was played by Jessica Steen. In the season 5 Atlantis episode "Ghost in the Machine", the consciousness of Elizabeth Weir, having been transferred to sub-space by a group of Replicators hoping to ascend, was transferred to a Replicator template, and portrayed by Michelle Morgan.

Role in Stargate