Semyon Zinovyevich Alapin (Russian: Семён Зиновьевич Алапин; 19 November [O.S. 7 November] 1856 in Saint Petersburg - 15 July 1923 in Heidelberg) was a chess master, openings analyst, and puzzle composer. He was a linguist, railway engineer and merchant (grain commodities).
Born in Saint Petersburg, Russian Empire on 19 November [O.S. 7 November] 1856, he was one of the strongest players in the Russian Empire in the late 19th century. He died in Heidelberg, Germany on 15 July 1923.
Today he is best known for his creation of opening systems in almost all major openings. Most of these are of little significance today, but Alapin's Variation of the Sicilian Defence is an important opening line that is often played by leading grandmasters.
List of openings named after Alapin
- Alapin's Variation of the Sicilian Defence: 1. e4 c5 2. c3
- Alapin's Opening in the Open Game: 1. e4 e5 2. Ne2!?
- Alapin's Gambit of the French Defence: 1. e4 e6 2. d4 d5 3. Be3!?
- Alapin's Defence of the Ruy Lopez: 1. e4 e5 2. Nf3 Nc6 3. Bb5 Bb4
- Alapin's Variation of the Caro-Kann Defence: 1. e4 c6 2. c3
- Alapin's Variation of the Dutch Defence (also known as the "Manhattan Variation"): 1. d4 f5 2. Qd3
- Alapin's Variation of the Queen's Gambit: 1. d4 d5 2. c4 e6 3. Nc3 b6
- Alapin Steinitz Variation of the Evans Gambit: 1. e4 e5 2. Nf3 Nc6 3. Bc4 Bc5 4. b4 Bxb4 5. c3 Ba5 6. 0-0 d6 7. d4 Bg4
- Sanders Alapin Variation of the Evans Gambit: 1. e4 e5 2. Nf3 Nc6 3. Bc4 Bc5 4. b4 Bxb4 5. c3 Ba5 6. 0-0 d6 7. d4 Bd7