The definition of ruthless is someone without compassion or who doesn't show mercy.
The definition of competitive is relating to a situation for a win, or having a strong desire to win or to be the best.
Extremely violent or injurious; cruel:
The definition of cruel is someone or something that deliberately causes pain or suffering.
Ready or willing to take issue or engage in direct action; militant
Without mercy; having, feeling, or showing no mercy; pitiless, cruel, implacable, etc.
Having or showing no mercy; cruel; relentless; pitiless
Find another word for dog-eat-dog. In this page you can discover 11 synonyms, antonyms, idiomatic expressions, and related words for dog-eat-dog, like: ruthless, competitive, vicious, brutal, cruel, aggressive, cutthroat, merciless, unmerciful, voracious and without mercy.