You are a criminal investigator.  Maybe police, maybe private detective, doesn’t matter in this context.

The victim and your only witness is unconscious, unable to say or tell you anything.  Because time is of the essence, you only have the basic medical report to go from.  When asked, you are told ‘patient presented with acute trauma to the right common iliac artery’.  You begin looking for a left-handed woman immediately, likely a romantic partner or romantic interest at least.

Why?

First, what is the nature of the injury?  Acute trauma.  This means that something very severe and abrupt happened.  If it was chronic, then it would be something that happened over time.  The use of acute suggests that this is an injury that was inflicted upon the person.  Trauma further suggests this.

Secondly, we have the site of the injury: the Common Iliac Artery.  The body’s main artery – the Aorta – travels down the center of the body and in the lower abdomen, it splits (the technical term is ‘bifurcates’).  One side goes left and the other side goes right.  This becomes the Common Iliac Artery.  Why ‘common’?  That’s because it will further bifurcate/split (becoming the Internal and External Iliac Arteries).  Why iliac?  That’s the name for the top of the pelvic bone, the Ilium (or Iliac bone).  And artery, of course, means that it is carrying oxygenated blood away from the heart.

But there’s more.  The Common Iliac Artery is imbedded deep into the body.  It’s nothing something that can be casually injured.  Or, if it was damaged, likely there would be more catastrophic damage.  A ruptured artery is about as bad as it comes, unless you are talking about organ failure.  And since the intestines and the kidneys are in that area, there’d be a lot more described.  The fact JUST the Common Iliac Artery was damaged, that it alone is stated is not meant to be demonstrative of the damage, that’s because it is the only damage on that magnitude.  The kidneys are fine (or, we can assume they are).  Everything is fine (comparatively), EXCEPT the artery.  So what does that tell us?

This was a violent attack.

Now, if the suspect was shot, that would be obvious.  It would also likely be the catastrophic damage from before.  Sure, the entry wound might be tiny but the exit wound would be another matter.  Likewise, there would be considerable internal damage due to the rotation and spiral of gunshots.  So that would suggest that this was a knife attack.  If not a knife, likely something similar.  No, we don’t know this, but we can assume it in the absence of additional evidence.

Thirdly, we have the side.  This was the right side of the body.  If we assume that our suspect stabbed the victim, then they would have been left-handed.  Why?  Because the damage was to the right side.  Could they be right-handed and merely held the knife in the left hand?  It’s possible but extremely unlikely, for several reasons.

The Common Iliac Artery is low in the abdomen, going in towards the pelvis.  It’s also beneath the ilium (the top of the pelvic bone.  If a person was stabbed from the side, they would have hit the victim’s arm or their hip bone (or stabbed at an extremely awkward angle, which isn’t impossible).  If they were stabbed from behind, the chance of hitting the artery is lessened while the likelihood of stabbing an organ like the kidneys or the liver goes up.

So if we assume this was a stab from the front, then the suspect was either left-handed or stabbed across the body.  That isn’t impossible either, but unlikely.  Crossing the body telegraphs the attack and increases the likelihood it could be defended.  It also isn’t instinctual, but something that requires training.  If we continue with the assumption that this was a stab wound, it is a poorly-aimed one.  Anyone with training, or even a familiarity with the body, would stab up into the body, not down, because of the mechanics of the blade and how we hold a knife in our hands.  Also, stabbing up would increase the likelihood of death because of the chances of puncturing the diaphragm or the lungs.

Fourth, we are looking for a romantic partner or romantic interest.  Why?  A left-handed woman stabbed our victim in the lower abdomen/pelvis.  This suggests she may not have been aiming for a vital body part so much as the phallus.  She was aiming to ‘decapitate his manhood’ as it were.  Given that he was stabbed from the front suggests his attacker was too close for him to effectively defend, or even anticipate the attack.

Now, is this a spotless evaluation?  No, of course not.  This is one assumption after another.  But they are educated guesses based off of learning and experience.  This is a whole lot of information to glean just from one single sentence: patient presented with acute trauma to the right common iliac artery.

This is why vernacular matters.

And this is why vernacular is useless.

Languages aren’t existing things, final and complete.  Languages are forever evolving concepts.  They are mutually agreed-upon constructs that all users contribute to and reinforce.  The rules of a language are as concrete and writ in stone as the laws of the land or the rules of a sport.  They are forever re-evaluated, re-considered, and subject to interpretation and change.

Languages are meant to do one thing: convey ideas.  Allow for, and facilitate, communication.  Short of spouting true gibberish, you can’t say something wrong, only say it inefficiently.  And this is why sub-communities have their own use of languages.  Right common iliac artery means an absolute mountain of information to someone steeped in medical terminology.  To a custodian or a lawyer?  It might as well be a foreign language.

When we study new languages, this is why it is important to not get caught up worrying about vernacular and terminology.  Learn nouns, learn specific words, but don’t worry abut learning whole lists of words.  Learn words you will use, learn words you will say.  You’ll get a LOT more mileage out of learning ‘please’ and ‘thank you’ then you will ‘homeostasis’.  ‘Left’ and ‘right’ will serve you a lot better than ‘avenue’.

Remember the purpose of language: to convey ideas.  Keep this goal in mind as you work to study the language.  What ideas will you need to convey?  That will depend on the context of your language use.  In other words, that depends on where and with whom you will be using the language?  Will you be visiting a group of medical students?  Then maybe knowing how to say ‘common iliac artery’ might be needed.  Are you going to be touring breweries in a foreign country?  You might want to learn some different words instead.

Many people get turned off to the idea of studying another language because they fear the rote memorization of words.  It isn’t the difficulty that dissuades them, it’s the boredom.  They are learning words they don’t use, for contexts they don’t know.  Learn words in a foreign language, sure.  Just learn word that interest you, for a context you will find yourself in.