Definition of "Spider" :

noun: predatory arachnid with eight legs, two poison fangs, two feelers, and usually two silk-spinning organs at the back end of the body; they spin silk to make cocoons for eggs or traps for prey

noun: a skillet made of cast iron

noun: a computer program that prowls the internet looking for publicly accessible resources that can be added to a database; the database can then be searched with a search engine