A fitting illustration of how those aged between seven and 13 have attempted to reclaim control of their lives in the face of COVID-19, "power" takes the crown from 2020 winner "virus".
It beat shortlisted candidates including "love", "kindness", "humanity", "environment" and the somewhat off-topic "dragon".
Oxford's publishing director Lee Walker said the analysis showed young Australians were using more language associated with activism.
"We noted the word 'power' was used in a variety of contexts that reflect the challenging times we've been living through and will continue to be challenged by into the future," he said.
"The COVID-19 pandemic, climate change and looking after our earth, how leaders use their power to influence change, and how children use their imaginations to express their thoughts and to process the complex world we live in."
Flinders University literacy expert Anne Bayetto said use of "power" had increased 61 per cent year on year.
Positivity and introspection were other themes to emerge from the study, which analysed the writing of students in years 3 to 8.
"We witnessed a significant change of mindset among students this year, especially when compared to last year, as the usage of the word happiness increased by 280 per cent."
Ms Bayetto said the more introspective language included words such as "believe", "wonder", "forget" and "remember".
The study looked at nearly 80,000 short stories and more than nine million words.
AAP with The PRoject.