Serpent
Part of speech: noun
Definition: A snake. A musical instrument in the brass family, whose shape is suggestive of a snake (Wikipedia article).
Example sentence: There is poison in the fang of the serpent, in the mouth of the fly and in the sting of a scorpion; but the wicked man is saturated with it.
Ophidian
Part of speech: adjective
Definition: Of or pertaining to the Ophidia; belonging to serpents.
Part of speech: noun
Definition: One of the Ophidia; a snake or serpent.