Don’t know vernix? You ought to know the word. You were born covered with the stuff. It’s a greasy, cheese-like slime that coats in patches a new-born baby’s skin.

Its full name in medicine is vernix caseosa, medieval Latin for ‘cheesy varnish.’

The natal function of vernix is to moisturize the skin of the fetus and to help it slide easily here and there in its “bag of waters,” the amniotic sac of the uterus. The fetus is protected and cushioned inside this fluid-filled bag. Vernix then assists the potential neonate to slip along in its passage through the narrow birth canal and possibly protect the emerging babe from bacterial infection by acting as a barrier ‘slip cover.’ Once upon a medical study, neonatologists claimed that vernix helped to “waterproof” the baby and thus prevent undue heat loss in the moments right after birth. Now they are not so sure of that claim.

          Newborn with vernix before it is washed off.

Fascinating Etymology
Medieval Latin vernix becomes Italian vernice, then into modern French as vernis and thence into modern English as varnish, its precise meaning. Its alternate medieval Latin forms, bernix and veronix suggest that Latin itself borrowed the word from Byzantine Greek Βερενίκη ‎Bereníkē, a then common given name for women, ancestor of today's Christian name Bernice. Le Robert’s Dictionnaire historique de la langue française (1994 edition) posits a Queen Berenice of a city in Cyrenaica, eastern coastal region of ancient Libya, where an odorous resin was first made.

Vernissage: from Coating Baby’s Skin to Coating Great Paintings
Maybe you know the familiar French art term vernissage? Also used in English, it’s an invitation, often to friends of the artist and art critics, for a private view of newly completed paintings at an art gallery, usually a day before the official opening. But originally le vernissage was “the varnishing day,” when painters, exhibitors or gallery employees could still retouch or varnish the paintings before the public saw them. The word is a derivative of French vernis ‘varnish.’

Now the Cheesy Bits
The second part of the scientific medical name, caseosa, means ‘cheesy, cheese-like, abounding in cheese,’ made up of the common classical Latin noun for cheese caseus, to which is added one common Latin adjectival suffix of bounty, -osus, -osa, -osum, an ending productive of hundreds of adjectives borrowed into English like glorious where Latin gloriosus originally literally meant ‘full of glory.’ The other common adjectival suffix of bounty in Latin in -undus, -unda, -undum giving eventually English forms like abundant, moribund and redundant.

Latin caseus ‘cheese’ was borrowed into many later European languages, perhaps the earliest appearance of the loanword was in West Germanic languages, to give Old High German kasi, modern German Käse, Dutch kaas and dialect kees, Old Frisian zise and finally modern English cheese! The word may have travelled to northern Europe as Germanic peoples learned the Mediterranean method of making solid cheese with rennet instead of the more primitive way using sour milk.

Centuries later the Latin word for cheese, caseus, was reborrowed for use in English scientific vocabulary, to give words like casein, proteins suspended in milk which coagulate with rennet. The English adjective caseous is still in use, often humorously, to denote something containing or made of any cheesy substance. The medical adjective caseous describes tissue that has disintegrated, as in the phrase caseous necrosis, where the dead cells have become cheesy in appearance.

On that tasty note we shall not indulge in low, tawdry puns and ask, “Who cut the cheese?” Instead, befitting the scholarly elucidation hereinabove set forth, we shall adopt the higher modes of comportment and silently, sternly take our modest leave.

Bill Casselman, December 05, 2016

Text copyright 2016 by William Gordon Casselman

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At the Wording Desk

Bill Casselman

we are all born covered with vernix!