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All Souls' Day

(Encyclopedia)All Souls' Day, Nov. 2 (exceptionally, Nov. 3), feast of the Roman Catholic Church on which the church on earth prays for the souls of the faithful departed still suffering in purgatory. The proper of...

earth, in chemistry

(Encyclopedia)earth, in chemistry, metallic oxide not readily reducible by chemical means, e.g., alkaline earths, rare earths, and alumina. The name is also applied to certain absorbent clays, e.g., fuller's earth,...

alkaline-earth metals

(Encyclopedia)alkaline-earth metals, metals constituting Group 2 of the periodic table. Generally, they are softer than most other metals, react readily with water (especially when heated), and are powerful reducin...

rare-earth metals

(Encyclopedia)rare-earth metals, in chemistry, group of metals including those of the lanthanide series and actinide series and usually yttrium, sometimes scandium and thorium, and rarely zirconium. Promethium, whi...

Labor Day

(Encyclopedia)Labor Day, holiday celebrated in the United States and Canada on the first Monday in September to honor the laborer. It was inaugurated by the Knights of Labor in 1882 and made a national holiday by t...

Lady Day

(Encyclopedia)Lady Day or Annunciation: see Mary. ...

Memorial Day

(Encyclopedia)Memorial Day, holiday in the United States observed in late May. Previously designated Decoration Day, it was inaugurated in 1868 by Gen. John A. Logan for the purpose of decorating the graves of Civi...

May Day

(Encyclopedia)May Day, first day of May. Its celebration probably originated in the spring fertility festivals of India and Egypt. The festival of the Roman goddess of spring, Flora, was celebrated from Apr. 28 to ...

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