1.
If you say that someone is ruthless, you mean that you disapprove of them because they are very harsh or cruel, and will do anything that is necessary to achieve what they want.
The President was ruthless in dealing with any hint of internal political dissent.
ADJ: oft ADJ in n [disapproval]
• ruthlessly
The Party has ruthlessly crushed any sign of organised opposition.
ADV: ADV with v
• ruthlessness
...a powerful political figure with a reputation for ruthlessness.
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2.
A ruthless action or activity is done forcefully and thoroughly, without much concern for its effects on other people.
Her lawyers have been ruthless in thrashing out a divorce settlement...
ADJ: oft ADJ in n
• ruthlessly
...a ruthlessly efficient woman.
ADV
• ruthlessness
...a woman with a brain and business acumen and a certain healthy ruthlessness.
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