A futile attempt by a weak entity to resist a powerful one; to make a hopeless stand against overwhelming force; an unequal struggle.
面对市场巨头的竞争，那家小企业知道自己的力量有限，但仍决定放手一搏，尽管这看起来像是虫臂拒辙。
Facing the competition from market giants, that small company knew its strength was limited but decided to give it a shot anyway, even though it seemed like an insect's arm trying to stop a chariot wheel.
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