In Elizabethan theater, a spectator who stood in the pit rather than sat in the galleries; a coarse, earthly, or unsophisticated person.
From 'ground' plus the diminutive suffix -ling, originally a theatrical term for those standing on the ground level rather than in elevated seating, came to mean a crude or common person.
Shakespeare insults his own audience in plays like 'Hamlet,' calling groundlings lovers of crude spectacle and vice—but ironically, groundlings were often more engaged and enthusiastic than wealthy box-seat spectators.
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