I don't know if this is nitpicky or not...but I am sure my fellow Wordcrafters can tell me.

I was at the Shedd Aquarium with my niece today, and one of their educators was showing us an anaconda. A visitor asked if it is "poisonous," and he replied that he didn't think any snake is "poisonous." That's because, he said, nobody uses the word correctly. He said that "poisonous" means that something causes sickness when it is eaten. However, snakes are "venomous" because they bite and inject the venom.

Is that how you understand it? When I look up "poisonous" snakes in Google, there were over a million sites listed.

nitpicky or not

Many a person has argued about the proper usage of venomous versus poisonous. If somebody were to shout "watch out for that poisonous snake you're about to step on" the pedant would probably pause to correct his interlocutor and be bitten by the venomous but discerning reptile.

The OED (online, draft revision June 2010) has poisonous as a synonym for venomous in its first definition.

quote:

Containing, or of the nature of, poison; having the properties of a poison; venomous.

with citations from the early 15 century to the late 20th.

But, I know how the pedantic herpetologist feels. Almost nobdy uses the word grammar in its "proper" meaning.

I think that if you were to put venom in a silver chalice and give it to a king (or a certain president) that it would be poisonous.

I've also heard this old argument before. It might even have cropped up on QI. It is something that people will argue about but personally I'd happily use either word.

quote:

But, I know how the pedantic herpetologist feels. Almost nobody uses the word grammar in its "proper" meaning.

I suppose I can understand that. I know I've looked up grammar when we've had some of those discussions, and I've found many dictionaries will include a broad meaning, such as: "The system of rules implicit in a language, viewed as a mechanism for generating all sentences possible in that language."

quote:

I think that if you were to put venom in a silver chalice and give it to a king (or a certain president) that it would be poisonous.

"Certain president?" Better be careful; I'm from Chicago.

The poisonous venom in a chalice reminds me of one of my favorite movies ("The Court Jester"): "The pellet with the poison's in the vessel with the pestle; the chalice from the palace has the brew that is true!"

Poison, toxin, and venom are often used interchangeably, but technically they are different. Here are some definitions.

biology-on-line

quote:

• Poison, venom. Poison usually denotes something received into the system by the mouth, breath, etc. Venom is something discharged from animals and received by means of a wound, as by the bite or sting of serpents, scorpions, etc. Hence, venom specifically implies some malignity of nature or purpose.
  
  
• toxins
  poisons produced by certain animals, plants, or bacteria.
  
  
• venom
  (Science: chemical) A toxic secretion in animals that is actively delivered to the target organism, either to paralyse or incapacitate or else to cause pain as a defence mechanism. Commonly include protein and peptide toxins.

OED Online

quote:

• poison
  Material that causes illness or death when introduced into or absorbed by a living organism, esp. when able to kill by rapid action and when taken in small quantity; a substance of this kind. Also (esp. in early use): a drink containing such a substance.
  
  
• toxin
  A specific poison, usually of an albuminous nature, esp. one produced by a microbe, which causes a particular disease when present in the system of a human or animal body.
  
  
• venom
  The poisonous fluid normally secreted by certain snakes and other animals and used by them in attacking other living creatures.
    The venom of snakes is secreted in a poison gland communicating with the fangs, through which it is ejected in the act of striking.

M-W

quote:

• 
  poison
  1 a : a substance that through its chemical action usually kills, injures, or impairs an organism b (1) : something destructive or harmful (2) : an object of aversion or abhorrence
  2 : a substance that inhibits the activity of another substance or the course of a reaction or process <a catalyst poison>
  
  
• toxin
  any poison produced by an organism, characterized by antigenicity in certain animals and high molecular weight, and including the bacterial toxins that are the causative agents of tetanus, diphtheria, etc., and such plant and animal toxins as ricin and snake venom.
  
  
• venom
  poisonous matter normally secreted by some animals (as snakes, scorpions, or bees) and transmitted to prey or an enemy chiefly by biting or stinging; broadly : material that is poisonous

Venomous snakes (poisonous snakes)
Poisonous Snakes - a technical misunderstanding

quote:

The correct term to use is venomous. Normally venom is harmless if ingested but if the venom is injected into some tissue it is toxic and the tissue around the site of injection and other parts of the body will suffer one way or another.

Wikipedia

quote:

Poison

In the context of biology, poisons are substances that can cause disturbances to organisms, usually by chemical reaction or other activity on the molecular scale, when a sufficient quantity is absorbed by an organism.

Legally and in hazardous chemical labeling, poisons are especially toxic substances; less toxic substances are labeled "harmful", "irritant", or not labeled at all.

In medicine (particularly veterinary) and in zoology, a poison is often distinguished from a toxin and a venom. Toxins are poisons produced via some biological function in nature, and venoms are usually defined as biological toxins that are injected by a bite or sting to cause their effect, while other poisons are generally defined as substances which are absorbed through epithelial linings such as the skin or gut.

Some poisons are also toxins, usually referring to naturally produced substances, such as the bacterial proteins that cause tetanus and botulism. A distinction between the two terms is not always observed, even among scientists.

Animal toxins that are delivered subcutaneously (e.g. by sting or bite) are also called venom. In normal usage, a poisonous organism is one that is harmful to consume, but a venomous organism uses poison to defend itself while still alive. A single organism can be both venomous and poisonous.

Toxin
A toxin (Greek: τοξικόν, toxikon) is a poisonous substance produced by living cells or organisms (although humans are technically living organisms, man-made substances created by artificial processes usually aren't considered toxins by this definition). It was the organic chemist Ludwig Brieger (1849-1919) who first used the term 'toxin'.

Venom
Venom is any of a variety of toxins[1] used by certain types of animals. Generally, venom is injected by such means as a bite or a sting. Poisons, by contrast, are eaten, inhaled, etc., by the victim.

Venomous snake
Venomous snakes are often said to be poisonous, although this is not the correct term, as venoms and poisons are different. Poisons can be absorbed by the body, such as through the skin or digestive system, while venoms must first be introduced directly into tissues or the blood stream (envenomated) through mechanical means. It is, for example, therefore harmless to drink snake venom as long as there are no lacerations inside the mouth or digestive tract. There are however two exceptions: the Rhabdophis snakes (keelback snakes) secrete poison from glands that it gets from the poisonous toads that it preys on; similarly certain garter snakes from Oregon retain toxins in their liver from the newts they eat.

Dictionary.com

Poison, toxin, venom  are terms for any substance that injures the health or destroys life when absorbed into the system, esp. of a higher animal.
Poison is the general word: a poison for insects.  

A toxin  is a poison produced by an organism; it is esp. used in medicine in reference to disease-causing bacterial secretions: A toxin produces diphtheria.

Venom  is esp. used of the poisons secreted by certain animals, usually injected by bite or sting: the venom of a snake.

This message has been edited. Last edited by: tinman,

Looking over the definitions it seems to be that poison is a more generic term and venom is a specific type of poison.

I see nothing wrong with substituting the generic term for the specific one where it is the generic aspect that we are referring to.

It's just another excuse for some pedants to get their knickers in a twist. I rather relish thought of zmj's pedant getting bitten instead of reacting in time. BTW, Bob, you're right - this was mentioned on QI.

Coincidentally last night I saw a repeat of the QI programme which mentions this. Alan Davies (unusually) forsaw the trap and mentioned venom instead. How true this is I've no idea (this is, after all, QI) but Stephen Fry said there is at least one poisonous snake - the Orange-bellied Garter Snake if I heard correctly. Apparently its flesh is poisonous because its main diet is a species of newt which is poisonous to us. How/why the newt is poisonous he didn't say.

There is certainly no reason for a layman to avoid using "venomous" and "poisonous" interchangably. But there are the differencesa already enumerated, using the correct terminology would be necessary for someone in a professional or techinical field. An instructor would fll into that category and, as a zoo docent, I was told by my teacher to be careful to differentiate when discussing that subject.