lodestone vs permanent magnet

lodestone and permanent magnet both are nouns.

Word	Noun	Adjective	Verb	Adverb
lodestone	Yes	No	No	No
permanent magnet	Yes	No	No	No

As nouns, permanent magnet is a hypernym of lodestone; that is, permanent magnet is a word with a broader meaning than lodestone:

lodestone: a permanent magnet consisting of magnetite that possess polarity and has the power to attract as well as to be attracted magnetically
permanent magnet: a magnet that retains its magnetism after being removed from a magnetic field

Other hypernyms of lodestone include static magnet.

lodestone (noun)	permanent magnet (noun)
a permanent magnet consisting of magnetite that possess polarity and has the power to attract as well as to be attracted magnetically	a magnet that retains its magnetism after being removed from a magnetic field