A person who occupies a position of authority or responsibility but does little meaningful work; someone who appears busy but is unproductive.
From 'chair' (seat of authority) + 'warmer' (one who warms through sitting). The term is metaphorical, using 'warming the chair' to suggest someone just sits there without contributing.
The term 'chairwarmer' is brilliantly contemptuous—it's a way of saying someone is just taking up space and using a position that someone more capable could fill, which is why it's considered a real insult in organizational contexts.
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