Desire, craving, or appetite; covers concrete wants (like appetite or material desire) as well as ambitions; often used as a suffix in compounds (e.g., 食欲).
最近、出世欲が強くなってきた。
Lately I've been feeling a stronger ambition to get ahead.
その薬は食欲を抑える効果がある。
That medicine has the effect of suppressing appetite.
人は欲に振り回されることがある。
People are sometimes driven by their desires.