instruction:
Generate a topic word for the given sentence. A topic word is usually the name of a person, place, animal, concept or object the sentence is focusing on.
question:
a dipole speaker is a type of a loudspeaker.
answer:
dipole speaker


question:
eosinophil granulocytes, usually called "eosinophils" or "eosinophiles", are granulocyte white blood cells that fight off certain parasites and infections in vertebrates.
answer:
eosinophil granulocyte


question:
the greco–persian wars were a series of wars fought between classical greece and persia's achaemenid empire in the 5th century bc.
answer:

greco–persian wars