We had a discussion over dinner yesterday about poisonous spiders.
Are they around us? How easy is it to run into one?
What is the most poisonous living thing on earth?

You might try a search: What’s the most poisonous creature on earth?

Or you might look on this Message Board and see other threads with this title, commenting on that column.

Poisonous spiders around us? I live in Australia, so yep. We have songs about deadly spiders awaiting us on the toilet seat, but mostly it’s a seat-up beat-up. The link to the mailbag item to which this comment refers is What’s the most poisonous creature on earth? If you haven’t seen it vanilla there is a thread around this topic here.


Cecil, ye’re getting sloppy! You, of all people, should have pointed out that a critter capable of killing with its venom is “venomous”, not “poisonous”. A “poisonous” fish, snake, insect, etc. is one that’s deadly to consume. Not the same thing at all – venomous rattlesnakes, for instance, aren’t the least bit poisonous if they’re cooked correctly.

DGW, congrats on your first post, and welcome to the Boards!

I just want to point out that Cecil has nothing to do with the Mailbag, except for tossing questions that he doesn’t want for his column to his loyal Straight Dope Science Advisory Staff. The Mailbag Answers are written by staff, and edited by Ed Zotti. The poison one was written by Doug (our resident bug guy), and I will call his attention to your comment.

Well, I don’t know how Bug Doug uses it, but the American Heritage Dictionary’s first definition of poisonous is “Having the capability of harming or killing by or as if by poison; toxic or venomous” and in the discussion of the synonyms poisonous, mephitic, pestilent, pestilential, toxic, venomous, virulent, AHD uses the example “a poisonous snake”.

I don’t doubt it – after all, we live in a world where the New York Times stylemeisters themselves have decreed that “preventative” is actually a word. So goes the decline of western civilization…

Is stylemeister a word?

While some people may use the terms that way, it’s by no means universal. For example, arachnologists frequently say that virtually all spiders (30,000 species!) are venomous, but only a handful are poisonous. That is, they’re venomous if they inject venom, but only the more lethal varieties are considered poisonous. Tarantulas, for example, are venomous but not poisonous.

Having said that, I recently read one book on tarantulas which said described them as being “poisonous” but non-lethal. I question the accuracy of this terminology, but perhaps it merely demonstrates that there’s no universally acceptable definition of this term.

You’ll note that I use the terminology “poisonous” only when referring to a substance, and “venomous” when referring to an animal. For me, “poisonous” is synonymous with “toxic”, and “venomous” means “produces venom”. I’m pretty sure I do not confuse the two terms in my posting.