# Did the definition of "mammal" change in the last ~30 years? **URL:** \ **Category:** Factual Questions\ **Created:** [August 15, 2010, 6:29pm UTC](https://boards.straightdope.com/t/did-the-definition-of-mammal-change-in-the-last-30-years/550342 "2010-08-15T18:29:58Z")\ **Posts on this page:** 4\ **Page:** 3
**Author:** ![naita](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/naita/32/5862_2.png) [@naita](https://boards.straightdope.com/u/naita)\ **Post date:** [August 16, 2010, 4:57pm UTC](https://boards.straightdope.com/t/did-the-definition-of-mammal-change-in-the-last-30-years/550342/41 "2010-08-16T16:57:17Z")
> [@Colibri](#): > > This is not really correct. In common usage, it is perfectly correct to refer to animals that inject toxins as poisonous. > > From [Merriam-Webster:](http://www.merriam-webster.com/dictionary/poisonous) > > > [@](#): > > > > Main Entry: poi·son·ous > > Pronunciation: \ˈpȯiz-nəs, ˈpȯi-zən-əs > > Function: adjective > > Date: 1565 > > 1 : destructive, harmful > > 2 : having the properties or effects of poison : venomous > > 3 : spiteful, malicious > > The distinction between venomous and poisonous you mention is made in some technical usages; it is not necessary in informal usage. It is perfectly correct to call a rattlesnake or a platypus poisonous. The dictionary isn’t really your friend there. It’s saying that one meaning of poisonous is “having the properties or effects of poison”, and that a synonym in that sense is venomous. The corresponding definition of venomous has poisonous as a synonym, but in the sense “having a venom-producing gland and able to inflict a poisoned wound” no synonyms are given. Which of course doesn’t mean you’re wrong, just that you shouldn’t have quoted that dictionary. ---
**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\ **Post date:** [August 16, 2010, 5:19pm UTC](https://boards.straightdope.com/t/did-the-definition-of-mammal-change-in-the-last-30-years/550342/42 "2010-08-16T17:19:23Z")
> [@naita](#): > > The dictionary isn’t really your friend there. It’s saying that one meaning of poisonous is “having the properties or effects of poison”, and that a synonym in that sense is venomous. The corresponding definition of venomous has poisonous as a synonym, but in the sense “having a venom-producing gland and able to inflict a poisoned wound” no synonyms are given. > > Which of course doesn’t mean you’re wrong, just that you shouldn’t have quoted that dictionary. Not at all; the two definitions confirm what I said. The full definition of venomous is: > [@](#): > > Main Entry: ven·om·ous > Pronunciation: \ˈve-nə-məs > Function: adjective > Date: 14th century > 1 :\*\* full of venom:\*\* as a : **poisonous,** envenomed b : noxious, pernicious \ c : spiteful, malevolent \ > 2 : having a venom-producing gland and able to inflict a poisoned wound \ > [@](#): > > Main Entry: 1ven·om > Pronunciation: \ˈve-nəm > Function: noun > Etymology: Middle English venim, from Anglo-French, from Vulgar Latin \*venimen, alteration of Latin venenum magic charm, drug, poison; akin to Latin venus love, charm — more at win > Date: 13th century > 1 : 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** > 2 : ill will, malevolence Bolding mine. In the broadest usage, venomous simply means “full of poisonous material,” as in Shakespeare’s “Sweet are the uses of adversity, Which, like the toad, ugly and venomous, Wears yet a precious jewel in his head.” (_As You Like It,_ Act II, Scene 1). While the distinction you mention is sometimes made, it is not a necessary one. It is correct to use poisonous and venomous as synonyms. ---
**Author:** ![naita](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/naita/32/5862_2.png) [@naita](https://boards.straightdope.com/u/naita)\ **Post date:** [August 16, 2010, 5:37pm UTC](https://boards.straightdope.com/t/did-the-definition-of-mammal-change-in-the-last-30-years/550342/43 "2010-08-16T17:37:07Z")
> [@Colibri](#): > > While the distinction you mention is sometimes made, it is not a necessary one. It is correct to use poisonous and venomous as synonyms. What the dictionary lacks is a definition for poisonous as “having a venom-producing gland and able to inflict a poisoned wound”. Unless you think m-w divided their definition for venomous into two separate meanings for fun, the meaning of venomous that the original nit-pick implies, doesn’t have poisonous as a synonym, and your original quote for the definition for poisonous only has poisonous as synonymous to venomous in the “having the properties or effects of poison”-sense. It might not be a necessary distinction and using poisonous and venomous as synonyms in all senses may be correct and universal, but saying that the dictionary doesn’t indicate otherwise is obviously wrong. ---
**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\ **Post date:** [August 16, 2010, 6:03pm UTC](https://boards.straightdope.com/t/did-the-definition-of-mammal-change-in-the-last-30-years/550342/44 "2010-08-16T18:03:18Z")
> [@naita](#): > > What the dictionary lacks is a definition for poisonous as “having a venom-producing gland and able to inflict a poisoned wound”. Why should it? It’s unnecessary to specify all possible meanings of “poisonous.” [QUOTE=naita] Unless you think m-w divided their definition for venomous into two separate meanings for fun, the meaning of venomous that the original nit-pick implies, doesn’t have poisonous as a synonym, and your original quote for the definition for poisonous only has poisonous as synonymous to venomous in the “having the properties or effects of poison”-sense. [/QUOTE] [QUOTE=WhyNot] Pedantic nitpick: animals that can kill you with a toxin by getting that toxin into you via injecting it through your skin are venomous, \*\*not poisonous. \*\*Poisonous is a plant or animal with a chemical that sickens or kills you when you ingest it or touch it. So a male platypus is venomous, **not poisonous.** [/QUOTE] Bolding mine. Sorry, you’re wrong. Of course the platypus is venomous in the sense of injecting its poison/venom. However, to say that for that reason it is _not poisonous_ is incorrect. It is both venomous, in the sense of injecting its poison, and venomous, in the sense of containing venom. It is poisonous in the sense of being harmful; and having the effects of poison (when it injects the venom). > [@naita](#): > > It might not be a necessary distinction and using poisonous and venomous as synonyms in all senses may be correct and universal, but saying that the dictionary doesn’t indicate otherwise is obviously wrong. The dictionary indicates that it is possible to make some distinctions; it does not indicate that the original nit-pick was correct. [Previous page](https://boards.straightdope.com/t/did-the-definition-of-mammal-change-in-the-last-30-years/550342.md?page=2)