Word To Use Today: venom.

 Venom is excreted by animals with the aim of poisoning other animals.

A snake's venom will often flow down through a grooved tooth that's been specially folded down into biting position. This venom will often be used to kill food, but the fact that a snake is known to be venomous means that predators - like humans - do tend to leave the reptiles alone.

On the other hand, it also means that humans, being essentially unobservant, are inclined to kill all snakes, even the non-venomous ones, if they can do so safely. Just in case.

Insect venom is sometimes mouth-delivered in much the same way, but a scorpion's sting is in its tail, and a centipede's venom is delivered through a modified leg. A caterpillar's venom might be delivered through a bristle, and a wasp's venom, delivered from its rear end, actually has a smell that attracts other wasps to come and join the attack. On the other hand, there are ants which rub their venom on themselves to cure their own diseases.

About the most deadly venom is excreted by the box jellyfish, Malo kingi. The beast is about the size of a fingernail. 

(Good grief, I might never go in the sea again. And, I mean, there are loads of venomous fish, too. Eerk!)

A toad's venom is most likely to be excreted through its skin. Sometimes this venom will kill an attacker, but sometimes it just tastes absolutely disgusting, or causes non-life-threatening but very unpleasant symptoms which will quickly make a predator think better of eating it - and afterwards think better of trying to eat any other toad, as well. 

Some salamanders, when under threat - and this is really James Bond - extrude venom-tipped ribs.

But, you know something? The most interesting thing about venom, as far as I'm concerned, is the word's derivation.

Word To Use Today: venom. This word comes from the Old French venim, from the Latin word venēnum, which means poison or love potion and is related to the word Venus, who is the goddess of love.

(Yes, I know it's April Ist, but this is all really true!)