Lise Meitner (November 7, 1878 – October 27, 1968) is an Austrian physicist who works on radioactivity and nuclear physics.

Meitner is part of the team that discovers nuclear fission, an achievement for which her colleague Otto Hahn is awarded the Nobel Prize.

Meitner is often mentioned as one of the most glaring examples of women's scientific achievement overlooked by the Nobel committee.

A 1997 Physics Today study concluded that Meitner's omission was "a rare instance in which personal negative opinions apparently led to the exclusion of a deserving scientist" from the Nobel.

Element 109, meitnerium, is named in her honor.