Difference between Unmerciful and Tigerish

UNMERCIFUL vs TIGERISH: ADJECTIVE

Unconscionable; exorbitant.
Not merciful; not influenced by mercy; unkind; cruel; inhuman; merciless: of persons or things.

Heartless, Cruel, Unforgiving, Brutal, Relentless, Unpitying, Bowelless, Cutthroat, Tigerish, Fierce, Mortal, Ruthless, Remorseless, Pitiless, Merciless

Unrelenting, Remorseless, Fearless, Fierce, Ruthless, Feisty, Steely, Fearsome, Indomitable, Relentless, Tenacious, Nerveless, Ferocious, Unmerciful, Merciless

Heartless, Cruel, Unforgiving, Brutal, Relentless, Unpitying, Bowelless, Cutthroat, Tigerish, Fierce, Mortal, Ruthless, Remorseless, Pitiless, Merciless

Unrelenting, Remorseless, Fearless, Fierce, Ruthless, Feisty, Steely, Fearsome, Indomitable, Relentless, Tenacious, Nerveless, Ferocious, Unmerciful, Merciless

Thank you Great Spirit for your Unmerciful Treatment, I am waiting for you to return.
God, despiteful, proud, boasters, inventors of evil things, disobedient to parents, without understanding, covenant breakers, without natural affection, implacable, unmerciful.
Either these laws are barbarous or the transportation is unjust and unmerciful to those living out of the State.
Undoubtedly to some, the idea of giving so much love to self will seem very cold, hard and unmerciful.
Through the parable of the unmerciful servant, the Savior taught why we must forgive others.
Far be it that we should ever think such an iniquity that God could become unmerciful!
Coston, who was in the habit of prefacing breakfast with prayers of unmerciful length.
Unfortunately some of the priest unmerciful in the continued abuses.
Vicious Rumors offers up an unmerciful audio thrashing on the listener with Razorback Killers.
The dead and disturbed are unmerciful in their revenge!

They have perpetrated several murders, perhaps, and then come to the new country with a tigerish appetite for blood, whetted by their previous experience.
The future Leicester centre was certainly not exactly tigerish in the classroom.