O. Henry, pseud. of William Sydney Porter, 1862–1910, American short-story writer, b. Greensboro, N.C. He went to Texas in 1882 and worked at various jobs—as teller in an Austin bank (1891–94)...

O Salutaris Hostia [Lat.,=O saving victim], hymn to the Host, one of the two hymns regularly sung at the Benediction of the Blessed Sacrament in the Roman Catholic Church. The other hymn is Ta...

Man o' War, 1917–47, American racehorse, by Fair Play out of Mahubah, bred by August Belmont near Lexington, Ky., and owned by Samuel D. Riddle after 1918. A large reddish-colored colt capable...

Selznick, David O., 1902–65, American film producer, b. Pittsburgh. He worked for studios in Hollywood before founding Selznick International Pictures in 1936. Selznick's most famous movie is ...

Matthiessen, F. O. (Francis Otto Matthiessen), 1902–50, American critic, b. Pasadena, Calif., grad. Yale Univ., 1923, B.Litt., Oxford, 1925, Ph.D., Harvard, 1927. A Rhodes Scholar at Oxford, h...

Simpson, O. J.(Orenthal James Simpson), 1947–, American football player, b. San Francisco. As a running back for the Univ. of Southern California, he won the Heisman Trophy as the best college...

Sodium thiosulfate, Na2S2O3, colorless crystalline compound that is more familiar as the pentahydrate, Na2S2O3·5H2O, an efflorescent, monoclinic crystalline substance also called sodium hyposu...

Ferrous sulfate or iron (II) sulfate, chemical compound, FeSO4. It is known as the monohydrate, FeSO4·H2O; the tetrahydrate, FeSO4·4H2O; the pentahydrate, FeSO4·5H2O; and the heptahydrate, FeS...

Periodic Table of the Elements: OxygenAtomic Number:8Atomic Symbol:OOxygenAtomic Weight:15.9994ElectronConfiguration:2 · 6

Te Deum laudamus [Lat.,=we praise Thee, O God], early chant of the Western Church beginning, We praise Thee, O God, we acknowledge Thee to be the Lord. Legend ascribes it to an ecstatic outbur...