According to Oxford Corpus, a database containing hundreds of millions of words of written English, the usage of the term "climate emergency" increased steeply over the course of 2019, and by September it was more than 100 times as common as it had been in the previous year.
The phrase has risen from "relative obscurity to becoming one of the most prominent - and prominently debated - terms of 2019," said Oxford.
Climate emergency is defined as "a situation in which urgent action is required to reduce or halt climate change and avoid potentially irreversible environmental damage resulting from it," according to Oxford.
Oxford said the choice was reflective, not just of the rise in climate awareness, but the focus specifically on the language we use to discuss it. The rise of "climate emergency" reflected a conscious push towards the language of "new gravity and greater immediacy."
In 2019, "climate" became the most common word associated with "emergency," three times more than "health emergency," the second-ranking term.
Every year since 2004, Oxford Dictionaries would select a word or expression that has attracted the most interest over the past 12 months. The winner is chosen based on data of its usage and other indicators of the word's cultural impact.
Previous words of the year include "toxic" in 2018, "youthquake" in 2017 and "post-truth" in 2016.