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.

a dipole speaker is a type of a loudspeaker.
dipole speaker

the sunflower ("helianthus annuus") is a living annual plant in the family asteraceae, with a large flower head ("capitulum").
sunflower

palombia is a fictional country, between paraguay and colombia.

palombia

