Omicron (Ο or ο) is the 15th letter of the Greek alphabet.
Omicron, Omikron, Ο or ο may also refer to:
Science SARS-CoV-2 Omicron variant, a variant of the virus that causes COVID-19 Omicron (wasp), a genus of wasps Polynucleobacter necessarius, a bacterium originally designated as Omicron (German: )
Other uses ο, , , the number 70 in ancient, Byzantine and modern Greek numerals Omicron (film), a 1963 Italian film Omicron Hill, a summit in Alaska, US Omikron: The Nomad Soul, an adventure video game
See also
Omikronpapillomavirus, a genus of viruses
(omicron) (omicron) O (disambiguation) Omnicron (disambiguation)