The official residence of the Prime Minister of Canada. / (metonymically) The Canadian Prime Minister's Office or the federal government of Canada.

24 hours per day, five days per week (implicitly weekdays: Monday through Friday). Designates a round-the-clock service during the week, but excluding weekends.

Abbreviation of twenty-four seven.

Abbreviation of twenty-four seven.

(pathology) Abbreviation of non-24-hour sleep-wake rhythm disorder.

plural of 24-cell

(geometry) A four-dimensional polytope whose twenty-four bounding facets are octahedra and which has no three-dimensional analogue.

(physics) The major stable isotope of magnesium, ²⁴₁₂Mg, having twelve protons and twelve neutrons; it amounts to about 79% of the element in nature

(Canada) The office of Prime Minister of Canada.

Former name of 24 Sussex Drive.