Masruq (may Allah have mercy on him) says: I went to Sayyidah Aishah (may Allah be pleased with her) on the Day of Arafah, and she said: Give Masruq sawiq to drink and add plenty of sweetening to it. He says: I said: Nothing kept me from fasting today except that I feared it might be the Day of Sacrifice (Nahr). Sayyidah Aishah (may Allah be pleased with her) said: Nahr is the day on which the people sacrifice, and Fitr is the day on which the people break the fast.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصيام / 8209