Context: Nirvana (Sanskrit; Pali: "Nibbāna") means "cessation", "extinction" (of craving and ignorance and therefore suffering and the cycle of involuntary rebirths (saṃsāra)), "extinguished", "quieted", "calmed"; it is also known as "Awakening" or "Enlightenment" in the West. The term for anybody who has achieved nirvana, including the Buddha, is arahant.

Question: What is the term for someone who has achieved nirvana?

Answer: arahant