'balk' originates from Old English, specifically the word 'balca' (or 'bealc'), where the root meant 'ridge' or 'bank' (a strip or beam-like piece of land).

'balk' changed from the Old English word 'balca' meaning a ridge or beam into Middle English 'balk(e)' and later developed the verbal sense 'to place an obstacle in the way' or 'to stop short', eventually becoming the modern English verb 'balk'.

Initially, it meant 'a ridge, beam, or strip of land,' but over time it evolved into its current verbal meanings of 'to stop short; to refuse' and 'to thwart or obstruct'.