The long and short of “omicron”

Big concerns—and confusion—over a “little o.”

Short o as in not, long o as in note. This distinction, which many of us learn in our earliest days of hacking through the thickets of reading and writing in English, is at the center of a term very much in the news—omicron, the latest named variant of the Covid-19. (Why Greek letters are used to name Covid-19 variants.)

The variant is causing, of course, great health concerns across the globe, but it is also causing—far less gravely—confusion over the word’s pronunciation.

Origins of omicron

Omicron (O, o) is the name of the 15th letter of the Greek alphabet and comes from the Greek ο μικρόν (o mikrón), literally meaning “small o.” This so-called “small o” stands in contrast with omega (Ω, ω), the 24th and final letter of the Greek alphabet and which literally means “great o,” from the Greek ω μέγα (o méga). 

The letter omega was developed in ancient Greek around 600 BC, representing a long o sound. Before then, omicron—ultimately from a Phoenician and Semitic character for a guttural sound, ayin, meaning and originally depicted in the shape of an “eye”—was used for both short and long o’s in the language. Omicron was passed down to the Latin alphabet, and from there onto our own, where it occupies that same 15th slot as in Greek.

You may recognize descendants of the Greek mikrón in micro, which means “extremely small” in English and mostly seen in combination with other words and word forms, such as microbiology, micrometer, and microscope. 

And méga? It lives on in mega, meaning “very large,” and also seen in other words, like megahertz and megapolis. While the deeper roots of mikrón are obscure, méga is traced back to the Proto-Indo-European *meg-, “great,” source of such words as mickle and much (Old English); magnitude, magnify, major, and majesty (Latin); and mahatma and Mahabharata (Sanksrit). 

Both omicron and omega are recorded in English around the 1400s, with omega figuratively meaning “the last of anything” due to its alphabetical position. It was notably used by, of, and for God in Revelations 1:8: “I am the Alpha and the Omega,” or the beginning and the end.

Omicron (pronunciation) variants

The exact phonetic values of the vowels omicron and omega in ancient Greek are a more complex matter, but they are generally given as the o in hot and hope, respectively. I should note here, too, that what we refer to as short and long vowels when teaching people how to read in English is different than what linguists mean by vowel length. 

Fast forward to today: in American English, omicron can be variously pronounced as [ om-i-kron ] or [ oh-mi-kron ]. The former pronunciation features what we commonly refer to as a short o, the latter a long o; in both cases, the stress falls on the first syllable. British English allows for more pronunciations, including [ om-i-kron ] but also [ oh-mahy-kron ], which has a long o—and a long, stress-bearing i. 

Scions of psilon

Omicron and omega aren’t the only Greek letters hiding secrets to their historical pronunciation in their names.

Epsilon (E, ε)—the fifth letter of the Greek alphabet and ancestor of our fifth-letter e—is from the Greek ἒ ψιλόν (e psīlón), literally meaning “bare or simple e.” This name was meant to distinguish the letter from the same-sounding diphthong spelled ai.

And upsilon (Y, υ)—the 20th letter of the Greek alphabet and progenitor of both our letters u and y—is from the Greek ὖ ψιλόν  (ŷ psīlón)—meaning “bare u,” also apparently in distinction to a diphthong. 

The Greek ψιλόν (psīlón), as you’ve likely gathered, means “bare.” It also means “smooth, simple, mere.” According to the OED, it comes from the base of the verb ψίειν, essentially meaning “to feed on baby food.”

Here’s to hoping the Omicron variant proves as mild as just that—baby food.

m ∫ r ∫