what does it mean to welch on a bet
Welsh (surname) A related colloquialism is the verb to welsh/welch ('to renege') as in 'to Welsh/welch on a deal or bet', which may be derived from an age-old 'English' stereotype of the Welsh/Celtic peoples as unreliable oath-breakers, though that etymology remains conjectural.[1] The potential association with a negative stereotype results in it being considered a somewhat pejorative term.