What does "lightweight" mean?

Lightweight: (a) In boxing, wrestling, etc., one weighingnot more than 133 pounds (U. S. amateur rules 135 pounds, Eng. 140 pounds). (b) A person of small impotance or mental ability. [Colloq., Chiefly U. S.]

Additional senses

  1. 2.Light in weight, as a coin; specif., applied to a man or animal who is a lightweight.

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