Musannaf Ibn Abi Shayba 33:776

Abu Mu'awiyah narrated to us, from al-A'mash, from Mujahid, from 'Ubayd ibn 'Umayr, regarding His saying: "Al-ba'sa' (poverty/distress) and al-darra' (harm/adversity) touched them." He said: "Al-ba'sa' is misery, and al-darra' is harm." Then he said: "Al-sarra' is ease, and al-darra' is hardship."