(Le) [or la Reine] s'avisera. This is the royal veto, last put in force March 11, 1707, when Queen Anne refused her assent to a Scotch Militia Bill.
During the agitation for Catholic emancipation, George III. threatened a veto, but the matter was not brought to the test.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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