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a person who lacks the courage to do or endure dangerous or unpleasant things.

｟非難して｠ 臆病［卑怯（ひきょう）］者 (!時に呼びかけで)

1. literary excessively afraid of danger or pain.

2. Heraldry (of an animal) depicted with the tail between the hind legs.

Middle English: from Old French couard, based on Latin cauda ‘tail’, possibly with reference to a frightened animal with its tail between its legs, reflected in coward (sense 2 of the adjective) (early 16th century).