The term had the most online dictionary look-ups of any word, Merriam-Webster said on its website, after a year in which at least 1.4 million people globally have died from the COVID-19 pandemic.

"Sometimes a single word defines an era, and it's fitting that in this exceptional - and exceptionally difficult - year, a single word came immediately to the fore," the dictionary publisher said.

Pandemic is defined as "an outbreak of a disease that occurs over a wide geographic area (such as multiple countries or continents) and typically affects a significant proportion of the population", according to Merriam-Webster.com.

The word's Greek roots are "pan", meaning all or every and "demos", meaning people, Merriam-Webster said.

Dictionary searches skyrocketed on March 11 when the World Health Organisation officially labelled COVID-19 a pandemic.

The word "saw the single largest spike in dictionary traffic in 2020, showing an increase of 115,806 per cent over look-ups on that day in 2019", the company said.

Last year's winner was "they" as used to describe someone who does not identify as male nor female.

Australian Associated Press