Pain of mind on account of something done or experienced in the past, with a wish that it had been different; a looking back with dissatisfaction or with longing; grief; sorrow; especially, a mourning on account of the loss of some joy, advantage, or satisfaction. "A passionate regret at sin." "What man does not remember with regret the first time he read Robinson Crusoe?" "Never any prince expressed a more lively regret for the loss of a servant." "From its peaceful bosom (the grave) spring none but fond regrets and tender recollections."