'abreact' originates from German, specifically the word 'abreagieren', where 'ab-' meant 'away' and 'reagieren' meant 'to react'.

'abreagieren' transformed into the English word 'abreact', and eventually became the modern English word 'abreacting' through the addition of the present participle suffix '-ing'.

Initially, it meant 'to react away', but over time it evolved into its current meaning of 'to release an emotion by acting it out'.