Omicron is the new Covid variant hitting the headlines, having been named after a letter of the Greek alphabet.
It joins Alpha and Beta, which were named after the WHO announced it would call variants by Greek alphabet letters in May 2021.
This method replaced referring to variants by where they came from - last year a variant discovered in Kent became known as the "Kent variant".
However, the WHO said that this often led to unfair discrimination against places where the variants were identified, prompting them to change approach.
Here's what you need to know about how the letters are decided and how to pronounce Omicron...
How do the WHO decide which Greek letter to use for variants?
Currently there are five different prominent variants named by the Greek alphabet:
- Alpha
- Beta
- Delta
- Gamma
- Omicron
These variants all have scientific names consisting of letters and numbers, however the WHO decided to use Greek alphabet letters as they are more memorable for the general public as well as being easier to say.
Speaking on their decision to change the names of variants to Greek letters, the WHO said: "While they have their advantages, scientific names can be difficult to say and recall, and are prone to misreporting.
"As a result, people often resort to calling variants by the places where they are detected, which is stigmatising and discriminatory."
Why is it called Omicron?
There are some other variants named by Lambda and Mu, but these variants are less common.
The WHO however chose to skip "Nu" and "Xi" when naming the new variant.
Explaining the reason for the decision, it said "Nu" sounded too much like "new" and "Xi" is too commonly used as a surname.
How to pronounce Omicron in UK?
There has has been debate over how to say Omicron, however most people suggest saying it like it is written in English.
The phonetics vary according to different sources but many people pronounce it like o-mi-cron, with a small "o" sound rather than a capital "OH" sound.
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