Hawzah News Agency – The merciful prophet of Islam (pbuh) says: 

إنّما سُمِّيَ الرَّمَضانُ لأنّهُ يَرمَضُ الذُّنوبَ.

'Verily Ramadan has been thus named because it scorches away sins.'

Source: Kanz al-Ummal, no. 23688