In recent years, the word yikes has, along with oof, been ubiquitously adopted by Gen Z kids to express reaction to unpleasant situations. It's been used in this context for centuries, but just recently got so popular - according to my recollection and Google Trends, this meteoric increase in usage only took off in 2017. The earliest recorded attestation of yikes with its current definition is from 1953, but it was in use since the eighteenth century as a cry of general excitement. It's possible that yikes originated from yoicks, a fox-hunting cry used to rile up the dogs during a chase. That could even further come from hoicks and hyke, which were deer-hunting cries, but beyond that the origin is unknown. Alternatively, yikes might be an alteration of yipes, a similar vociferation which is imitative of a dog's noises, and some sources even suggest that yikes could be a conflation of both possibilities. The etymology is shrouded in uncertainty, but all prospects are intriguing. It'll be fun to watch yikes develop even further with time!
Adam Aleksic, a rising sophomore studying linguistics and government at Harvard University, has been described as the internet's sixth most famous etymologist. He also has disturbing interests in politics, vexillology, geography, board games, conlanging, and law.