A person who grapples; someone skilled in wrestling or hand-to-hand fighting, or someone who struggles with a difficult problem.
From 'grapple' + '-er' suffix (denoting an agent or person who does something). This agent noun developed naturally as grappling became a recognized activity.
Professional grapplers—whether wrestlers or people tackling intellectual problems—share a mentality of not giving up even when deeply engaged, which is why the word applies from sports to philosophy.
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