The meaning of emojis changes depending on the context in which they’re used and when they’ve been posted, according to the first study of their use over time.

Alexander Robertson at the University of Edinburgh, UK, and his colleagues tracked how emojis were used between 2012 and 2018 by Twitter users. In all, 1.7 billion tweets were checked to see if they contained an emoji, with duplicate content and non-English tweets filtered out.

The tweets were then analysed with models that recognise the semantics of how words are used based on others around them. This allowed them to attribute meanings to emojis and note changes to those meanings.

“We found patterns we would also find in words,” Robertson says. In the same way that words change meaning through usage, so do emojis. “You have seasonality in emojis,” he adds. For instance, the maple leaf emoji was most used in conversations about autumn during those months, while for the rest of the year it became a substitute for mentions of cannabis.

Read more: Say it with feeling: The complex world of emojis

The four emojis that changed meaning most over the study period were fingers pointing left, right and down, and a fist bump. For example, over time, the fist bump changed from signifying a willingness to fight, to being used to support movements such as Black Lives Matter. “What seems to stand out about the most variable ones is they can be used in a variety of situations,” says Robertson.

Effie Le Moignan at Newcastle University, UK, believes the work is a valuable contribution to the study of online language use, but that the findings have limitations. “This does not generalise beyond Twitter – which sounds so obvious,” she says. “But it’s such a crucial thing that platforms, and platform use, are distinctive.”

Le Moignan also thinks social media and linguistic experts could help parse the data in more detail. “If you map to closest words, the pairings may remain matched, but language use online is also flexible and evolving,” she says. For example, the word “tea” has evolved to mean gossip in online vernacular. Seeing a word next to an emoji “does not guarantee in the weird world of the internet the meaning didn’t alter over the time you collected data”, she says.

Robertson plans to go on to look at the layering of the meanings of emoji in their context.

Reference: arXiv, arxiv.org/abs/2105.00846