30,661 English Words Starting With O

Definition: 1. A blood type that has no antigens. It lacks the A, B and Rh factors on the blood cells. It is the universal donor for blood and can give blood to any blood type, but can only receive O- blood.

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Definition: 1. Alternative form of Echeng.

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Definition: 1. (informal) Organic chemistry.

There are 3 definitions of the word o-chem

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Definition: 1. Alternative form of Ezhou.

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Definition: 1. (informal) The wee hours.

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Definition: 1. (slang) The facial expression made during orgasm.

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Definition: 1. plural of o-face.

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Definition: 1. (slang) Alternative spelling of oh for.

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Definition: 1. plural of o-fer.

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Definition: 1. (Indo-European studies) In Proto-Indo-European linguistics, an ablaut form of a Proto-Indo-European root, characterised by the presence of the */o/ vowel phoneme in place of */e/.

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Definition: 1. Alternative form of ǃOǃKung.

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Definition: 1. A subject-based qualification superseded in England by GCSEs, but still available as an international examination.

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Definition: 1. plural of O-level.

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Definition: 1. A random fortune on a strip of paper, available from Shinto shrines and Buddhist temples in Japan in exchange for a small offering.

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Definition: 1. (US, regional, equestrianism) Gymkhana.

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Definition: 1. Alternative form of ooaa.

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Definition: 1. Alternative form of ooaa.

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Definition: 1. A circular gasket, usually made of rubber.

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Definition: 1. plural of O-ring.

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Definition: 1. Pronunciation spelling of alright.

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Definition: 1. (electronics, informal) oscilloscope

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Definition: 1. Shaped like the capital letter "O", circular.

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Definition: 1. (medicine) Short for orgasm shot.

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Definition: 1. (linguistics) A word, especially a noun in Indo-European linguistics, whose stem ends in /o/.

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