A person who makes broad conclusions or statements from limited examples, or who tends to think in general terms rather than details.
From generalise (British spelling of generalize) plus -er suffix meaning 'one who does.' The root traces to Latin generalis.
In philosophy and science, a 'generaliser' can be either brilliant or problematic—the same person who notices patterns others miss might also jump to conclusions too quickly! This is why the scientific method insists on rigorous testing rather than letting generalisers run wild.
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