Chessopedia: Online Chess Encylopedia

in "O"
  • O'Kelly de Galway, Alberic

    • 24 Reads
    • | 24 Reads

    Alberic O'Kelly de Galway (1911-1980) was a Belgium grandmaster (1956).  In 1962 he became the first grandmaster of over-the-board and  correspondence chess.  He was winner of the 3rd World Correspondence Championship (1962-1965... Read More »

  • Old Indian Defense

    • 5 Reads
    • | 5 Reads

    The Old Indian Defense is a chess opening defined by the moves: 1. d4 Nf62. c4 d6This opening is distinguished from the King's Indian Defense by Black developing his king's bishop on e7 rather than the fianchetto at g7. Mikhail Chigo... Read More »

  • Oll, Lembit

    • 1 Read
    • | 1 Read

    Lemibt Oll was born in April 23, 1966 in Hohtla-Jarve, Estonia.  In 1982, he was chess champion of Estonia.  In 1983, he was awarded the International Master title.  In 1984, he was junior champion of the USSR.  From 1992 through 1998, he play... Read More »

  • On a Hook

    • 2 Reads
    • | 2 Reads

      Read More »

  • open-closed

    • 107 Reads
    • | 107 Reads

    Open and Closed positions refer to the two main types of pawn structures of the centre . Open positions generally have an open centre , where the majority of the pawns have been swapped off . For example Scotch game results in an open game : ... Read More »

  • Opposition

    • 4 Reads
    • | 4 Reads

    Opposition is a common theme in end-games.Following is an example of opposition: Read More »

  • Orangutan opening

    • 464 Reads
    • | 464 Reads

    This opening (1.b4), also known as Sokolsky's Opening or Polish Opening, got its name during the New York 1924 tournament, when grandmaster Tartakower visited the Bronx Zoo, encountering Suzan the orangutan.  The next day, in the 4th roun... Read More »


    • 12 Reads
    • | 12 Reads

    Sometimes a chess piece is overloaded by having more than one defensive job to do. The overworked piece can be exploited by capturing one of the pieces it is defending or occupying a square it is defending forcing it to leave its other defensive ... Read More »

  • overloading

    • 4 Reads
    • | 4 Reads

    It often happens that a piece may protect two or more objectives at the same time. When this happens we refer to that piece as being overloaded. Usually, when your opponent has an overloaded piece you can use it in your favor by performing powerfu... Read More »

  • Owen, John

    • 31 Reads
    • | 31 Reads

    John Owen was born in Staffordshire on July 1, 1827.  In 1851, he was ordained and became a vicar of Hooten, Chesire from 1862 to 1900.  He was a member of George’s Chess Club and was recognized as one of London’s strongest a... Read More »