People who have deep knowledge or training in one particular subject, skill, or field rather than knowing many subjects at a basic level.
From Late Latin 'specialis' meaning individual or particular, from 'species' (kind or type). The suffix '-ist' (person who does something) makes it 'one who specializes in a particular kind.'
Medicine dramatically reversed who doctors respect—medieval medicine valued the generalist 'physician who knew everything,' but modern medicine worships the cardiologist who knows hearts inside and out, showing how complexity forces specialization.
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