noun

• An adult female horse.
• (UK, derogatory, slang) A foolish woman.
• (obsolete or historical) A type of evil spirit formerly thought to sit on the chest of a sleeping person; also, the feeling of suffocation felt during sleep, attributed to such a spirit.
• (UK, Ireland, Commonwealth, colloquial) A nightmare; a frustrating or terrible experience.
• (planetology) A large, dark plain, which may have the appearance of a sea, such as those on the Moon
• (planetology) On Saturn's moon Titan, any of several lakes which are large expanses of what is thought to be liquid hydrocarbons.
• Obsolete form of mayor. [The chief executive of the municipal government of a city, borough, etc., formerly (historical) usually appointed as a caretaker by European royal courts but now usually appointed or elected locally.]
• Obsolete form of mair. [(Scotland, historical) Various former royal officials in the Kingdom of Scotland.]