To block a Bill. In parliamentary language means to postpone or prevent the passage of a Bill by giving notice of opposition, and thus preventing its being taken after half-past twelve at night.
“By blocking the Bill [he] denied to two million persons the right of having votes.” —Contemporary Review, August, 1884, p. 171.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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