Synonym of Gunpowder Plot.

petit treason

(law, archaic) The crime of a subordinate killing a superior (other than the sovereign, which would constitute high treason): a servant killing his master, a wife killing her husband, etc.; and, earlier, certain lesser crimes of subordinates against superiors.

(law) Anything that may be interpreted as equivalent to actual treason by leading naturally to it.

(UK, humorous) Fourth of July.

(UK, historical) Synonym of Guy Fawkes Day.