Coronavirus and COVID-19

Unfortunately, the words coronavirus and COVID-19 are among the most commonly used nowadays, and several of the people I teach online have asked me about their pronunciation. Specifically, how should these words be stressed? Here I try to give a succinct answer.

First let’s look at COVID-19. Expressions of this type ending in numbers generally have the main stress on that number. Examples would include

Air Force One
mp3
high five
Route 66
the G8

and also COVID-nineteen.

(Most speakers use the GOAT vowel in the first syllable of COVID, as in over, but a few British speakers use the short LOT vowel as in coffee.)

Coronavirus is a compound noun, made up of two other nouns, corona (Latin for ‘crown’) and virus. English compound stress is notoriously tricky, but the basic rule is for the main accent to go on the first word:

airport
seat belt
history test
interest rate

and coronavirus. (As far as pronunciation is concerned, it doesn’t matter whether compounds are written with a space or not. Indeed some are written variably: seat belt, seat-belt, seatbelt.)

This compound stress makes English different from many other languages, which would make the second word more prominent: coronavirus. Here’s an example of a BBC newsreader clearly putting the main stress on the first part:

The UK’s Chief Scientific Adviser says the coronavirus…

Several dictionaries show the English stress pattern, e.g. the Oxford Advanced Learner’s Dictionary:
and the CUBE dictionary, which I co-edit:
(Stress, of course, is assigned to a syllable rather than to a whole word; the primary stressed syllable of corona is the second syllable.)

Numerous illnesses have names which are compounds in English, such as

hay fever
flu virus
chicken pox

If, on the other hand, the first word is an adjective rather than a noun, then generally this is a phrase rather than a compound, and it’s the noun that will be pronounced more strongly: 

Spanish flu
acute appendicitis
nervous breakdown

There’s a parallel difference between cell phone and mobile phone. Cell is a noun, so cell phone is a compound. Mobile is an adjective, so mobile phone is not a compound.

(There are also cases of early-stressed adjective-noun compounds, like greenhouse and yellow fever. Note that in these cases the colour word has a specialized meaning and does not function in a straightforwardly descriptive way: a greenhouse is not itself green, and yellow fever is not itself yellow.)

If you’ve been following the English-language news, you may sometimes have heard native speakers saying coronavirus, with the main stress on virus. Typically this happens when the word has already been used several times in the immediate context – which, sadly, is very common at the moment. Shifting the main stress away from corona- signals that the word is ‘given information’, or already ‘on the mind’; it also introduces an element of phonetic variety. For example, here is the first use of the word coronavirus in the headlines at the beginning of a BBC news bulletin:

Later in the same bulletin, this correspondent deaccentuates corona-:

Nonetheless, if you use this word in English, it will always sound correct if you use the normal compound stress, as indicated in the dictionaries above, coˈronavirus.

Please take care and try to keep yourself and others well.