1. Perennial shrub having large star-shaped yellow flowers in narrowly pyramidal cymes
   - Hypericum ascyron, Hypericum pyramidatum

Type of: St John's wort

• Otto Loewi
• Otto Meyerhof
• Otto Neumann Sverdrup
• Otto Robert Frisch
• Otto the Great
• Otto von Bismarck
• Otto Wagner
• ottoman
• Ottoman dynasty
• Ottoman Empire
• Ottoman Turk
• Ottorino Respighi
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• yolk
• yolk sac
• yolked
• yolky
• yom
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• Yom Kippur War