A person or institution that teaches students intensively to pass exams, or someone who crams information into their head quickly.
From 'cram' (to stuff or prepare hastily) plus the agent suffix -er; a modern term reflecting the pressures of exam-based education.
The word 'crammer' exploded in Victorian England when exams became the gatekeeper to success—it's a linguistic marker of how education became competitive and test-driven.
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