One of the areas of linguistic research is devoted to the origin of language and the connection between our ability to speak with the size and structure of the brain. We know that it is mainly the left hemisphere that controls language, that a special center, called the Broca center after the name of its discoverer (it was located in 1861), processes language information, and that the brain of primates differs considerably from that of other animals. However, we cannot say whether a certain part of the brain evolved with the purpose of allowing us to express our thoughts in verbal form or whether it had always existed and was later used for speech. Nor is the relation between language and thought clear. If language is the external reality of thought, should we conclude that animals, including most primates, do not think? What is the definition of thought? This is the stuff the uneasy dreams and nightmares of linguists, philosophers, and anthropologists are “made on.” But for those who coined the word brain, such questions did not exist. They split the skulls of their enemies and saw gray matter oozing out of the once talkative heads, while the marrow of animals, as they had found out, was good to eat. In some languages, the same word means “brain” and “marrow.” Such is, for example, Russian mozg. Latin distinguished between cerebrum and medulla. The distinction has been preserved in most Romance languages, though in Modern Spanish, meollo, the continuation of medulla, has partly taken over for both.
Unlike the Romance words, most names for the brain in the Germanic languages trace to obscure etymons, Engl. brain being one of the hardest despite the fact that it has cognates in Frisian, Dutch, Low (northern) German, and some German dialects. Not unexpectedly, old scholars looked for some Greek sources of the Germanic noun. First phren (“mind” and “thought” are only some of its meanings; compare Engl. frenetic “frantic, frenzied”) was suggested, then bregma “top of the head; fontanel.” The brain-bregma etymology proved long-lived, and 19th-century researchers tried to reinforce it. Among other things, they cited the pair Gothic hwairnei “skull” ~ Old Icelandic hjarni “brain,” and indeed the connection between the words for “skull” and “brain” looks natural. (Gothic is a dead Germanic language recorded in the 4th century, that is, several hundred years earlier before the emergence of the first extant written monuments of English and German.)
Yet one can proceed from a different direction. At one time, brain was pronounced with g in the middle (its modern trace is i in -ai–; German has Bregen), a circumstance that justified the comparison Bregen ~ brain ~ bregma. The most ancient form of brain must have sounded approximately like bragna. And this is also how bran allegedly sounded millennia ago. Engl. bran is a borrowed word, though its source remains a matter of debate. Old French had bran “bran,” though Modern French bran means “excrement, muck, filth.” The earliest meaning of French bran seems to have been “refuse, rejected matter.” Alongside the French noun, we find Irish bran “chaff, bran.” This is the reason it is unclear what the lending language of Engl. bran was: French or Irish. The French word was probably of Celtic origin. Its expressive character (a “low” name for “refuse” or “rubbish”) must have made it popular among the Celts’ Germanic and Romance neighbors. Slang and obscenities cross language borders with amazing ease. As noted, those who coined and borrowed *bragna (asterisks mark words that have been reconstructed rather that attested) had often seen the inside, the “refuse” of heads and bones, and for them brain and marrow were nothing more than “gray matter.” From their perspective, brain, if at all usable, was only brains, a dish. Assuming that marrow (Old English mearg, in which r is from z that developed from s: compare Russian mozg, cited above), is akin to mast “fruit of forest trees as food for pigs,” its original meaning was “fat.” Marrow looked like fat and got a corresponding name. One of the British English regional words for “brain” is pash, otherwise defined as “rotten or pulpy mass; mud, slush.” This is not an isolated example. An old etymologist, a student of German, derived Bregen (the German cognate of brain) from Brei “mush, paste; porridge.” The derivation is wrong, but the idea is sound. In the remote past, people had no notion what function the brain has in the human organism. They saw “mush” and called it accordingly. Since brain was a borrowed word, those who began to use it, must at one time have had a native name for the content of heads. There are several available candidates, but we cannot be sure which one to choose.
One of the ideas present in Indo-European religion was that the gods and people used different names for the same objects. According to a Scandinavian myth, the world was made from the body parts and organs of the dismembered giant Ymir. His brain, called heili in Old Icelandic, became the sky. The origin of heili is unknown (this is not a surprise), but, characteristically, it is a different word from hjarni, the noun that 19th-century linguists compared with Gothic hwairnei. Heili was the designation of a primordial brain and perhaps aroused loftier associations; hjarni filled the skulls of mortals. (It gives me great pleasure to report that Modern Icelanders call the human brain heili and thus elevated our pulp to divine dimensions.) A leading modern etymologist thought that hjarni might be a cognate of the Icelandic word for “gray” and glossed hjarni as “gray matter.” I think he was mistaken, but he may have looked for an answer in the right direction. Hjarni, like German Hirn “brain” (a more common word is Gehirn), is more probably related to German Harn “urine”, whose original meaning was “bodily waste.” Such is my uncomplimentary picture of the human brain seen through the eyes of our ancestors.
Anatoly Liberman is the author of Word Origins…And How We Know Them. His column on word origins, The Oxford Etymologist, appears here each Wednesday. Send your etymology question to firstname.lastname@example.org; he’ll do his best to avoid responding with “origin unknown.”