The quality of holding together or forming a unified whole; internal unity and strength of connection.
From cohesive + -ness suffix. This noun form became standard in the 1800s as English needed a term for the abstract quality of cohesion in scientific and social contexts.
A famous study found that the cohesiveness of a military unit predicted survival better than training or equipment—soldiers who felt bonded to each other had better problem-solving abilities even under extreme stress.
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