(1) - Merciful (a.) Unwilling to give pain; compassionate. (2) - Merciful (a.) Full of mercy; having or exercising mercy; disposed to pity and spare offenders; unwilling to punish.
(1) - Merciless (a.) Destitute of mercy; cruel; unsparing; -- said of animate beings, and also, figuratively, of things; as, a merciless tyrant; merciless waves.