Ostara may refer to:

• the Old High German for "Easter", cognate to Anglo-Saxon Ēostre
• Ostara (Wicca), the Neopagan and Wiccan festival celebrated around spring equinox
• The asteroid 343 Ostara
• The American Artemis class attack cargo ship USS Ostara (1944–1946), named after the asteroid
• Ostara (magazine), a 20th-century occult publication of Lanz von Liebenfels
• Ostara (band), a neo-folk musical group
• Ostara (album), an album by The Wishing Tree
• Ostara Publishing, a British publisher
• Ostara Nutrient Recovery Technologies Inc., a Canadian company specializing in resource recovery from wastewater and sewage sludge treatment

• St. Doologue's
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• Std::pair
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• St Dunstan Church, Woking