It’s not clear who first tagged the elephant’s snout with the name “trunk,” but it seems to have happened sometime in the late 16th century. The first documented instance appears in the 1589 work by Richard Hakluyt, Principal Navigations: “The Elephant . . . With water fils his troonke right hie and blowes it on the rest.”

As with most etymologies, the precise reason trunk is used to denote an elephant’s proboscis is difficult to distinguish. Arguably the most reasonable theory is that it derives from the fact that just a few decades before “trunk” started getting applied to an elephant’s snout, it was also a word used to describe a pipe or hollow tube, such as a speaking tube or ear-trumpet.  For instance, in the 1546 John Bale work, The Acts of English Voltaries:  “The roode spake these wordes, or else a knaue monke behynde hym in a truncke through the wall”.

Similarly in the 1553 work by Richard Eden, A Treatyse of the Newe India (which was a translation of part of Cosmographia, by Sebastian Muenster), where it describes the tubes used for blow-guns “They… blowe them [arrows] oute of a trunke as we doe pellets of claye.”

This “blow gun / hollow tube” usage particularly fits with the aforementioned first known use of the word to refer to an elephant’s proboscis, “With water fils his troonke right hie and blowes it on the rest.”

This might all have you wondering how the “trunk” of a car got this name. (For the British readers, we’re referring to the boot of a car here.)

For this, we need to go back to the Latin truncus, “main stem or stock of a tree or human body.” This, in turn, gave rise to the Old French “tronc” (“alms box in a church, trunk of a tree, trunk of the human body, wooden block”) around the 12th century and then the English “trunk” around the 15th century.

It is the “main stem of a tree” definition that is important in this one. By the mid-14th century, this gave rise to wood chests or cases being referred to as “trunks,” presumed to be because they were made from wood from tree trunks.

Whatever the case, the first known instance of this definition of the word can be found in a 1462 receipt (Mann. & Househ): “Item, payd ffor a new tronke ffor my lord whych was delyvared to Willyam off Wardrope x. s.”

Fast-forward a little under a half century later and we find an advertisement in the November of 1929 Hearst International Magazine where an automobile is listed as coming standard with “Six wire wheels and a trunk rack”. The rear trunk rack eventually gave way to a built-in storage compartment in the same region of the car that itself was referred to as a “trunk” in North America.

Another interesting one is the use of “trunks” to refer to an article of clothing, such as swimming trunks or “shorts.” This general definition for the word seems to have popped up in the 19th century with the first reference in 1836 in the Pickwick Papers, “The appearance of Mr. Snodgrass in blue satin trunks and cloak, white silk tights and shoes, and Grecian helmet.”

As for specifically “swimming trunks,” we have the first instance appearing in a July of 1883 edition of the Pall Mall Gazette where it states, “Captain Webb attempted his perilous feat of swimming the Niagara Rapids… He wore a pair of silk trunks…”

In this case, it’s generally thought the definition either stems from the “hollow tube” idea, with the trunks having two hollow tubes to stick your legs through (hence “trunks” instead of “trunk”), or is referring to the fact that the shorts contain part of the base of the trunk of the body.

If you liked this article, you might also enjoy our new popular podcast, The BrainFood Show (iTunes, Spotify, Google Play Music, Feed), as well as:

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Bonus Facts:

• Another one-time name for the elephant’s trunk is “boss,” presumed to be short for “proboscis.” This was first attested in the 1594 Lectures on Jonah, “Curtius writeth of the elephant that he taketh an armed man with his hand… He meaneth the boss of the elephant, which he useth as men their hands.”
• There are no bones in an elephant’s trunk, which is a fusion of its nose and upper lip. The trunk can grow to about 6 feet long and can weigh 300 pounds. Using at least 40,000 different muscles, an elephant can lift over 700 pounds with its trunk.
• Elephants can pull up to two gallons of water into their trunks through their nostrils at a single time. Elephants can also use their trunks as snorkels, and breathe through them while the rest of their body is submerged.
• Asian elephants have a single fingerlike appendage on the end of the trunks for grasping, while African elephants have two. The latter can actually grasp things by pinching them, while the former curls the tip of its trunk around them.
• Elephants have a keener sense of smell than even a bloodhound with millions of receptor cells in their nasal cavities; they can even smell water from miles away.
• Elephant brains can weigh up to 11 pounds, and have more complex sulci (brain folds) than any other animals except whales. This probably explains why they choose to live in matriarchal societies. 😉  And if you’re wondering, elephants really do have exceptional memories.
• The elephant’s hippocampus (the seat of emotions) is also more developed than other animals, and they are known to feel compassion, self-awareness and even have a sense of humor of a sort. Elephants also recognize their reflections.
• Elephants communicate with infrasounds – those too low for human ears to hear. Their enormous ears also help elephants regulate their body temperature.
• An African elephant fetus gestates for 22 months, and expectant mothers have been observed eating certain plants to induce labor. At birth, baby elephants can weigh more than 200 pounds.
• Baby elephants suck their trunks (like baby humans suck their thumbs).
• The closest relative to the elephant is a small mammal, the rock hyrax, that is found in sub-Saharan Africa and the Arabian Peninsula.
• Male elephants leave the matriarchal herd at 12 years, live in bachelor herds where homosexuality is known to occur until they fully develop, but when they are fully mature, they typically live alone.
• About 30% of the world’s population of Asian elephants live in captivity, and they make up the lion’s share of the 12,000 to 15,000 captive elephants globally; only about 1,000 African elephants live in captivity.
• Elephants appear to understand death, will examine the bones and tusks of the dead, have been known to bury dead humans and even grieve when they lose a loved one.
• Because ivory is worth more than gold, and most poachers don’t receive prison sentences even when convicted, over 20,000 African elephants were killed in 2013 alone. Ivory accounted for more than one billion dollars in trade during the past decade.
• There are only 650,000 elephants remaining. The World Wildlife Fund has African elephants on their vulnerable species list, and Asian elephants are endangered.