What is anything that floors or upsets a person, as a blow that knocks him down; a conclusive answer or retort; a task that exceeds one's abilities. [Colloq.] called?

floorer — Anything that floors or upsets a person, as a blow that knocks him down; a conclusive answer or retort; a task that exceeds one's abilities. [Colloq.]. (Webster's 1913.)

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