jus in personam
See jus ad rem.

• mens rea
• mental disability
• mental disorder
• mental disorder impeding choice
• Mental Health Act Commission
• mental health treatment requirement
• Mental Health Tribunal
• MEP
• mercantile agent
• mercenary
• merchantable quality
• merchant shipping registration
• mercy
• mere equity
• merger
• Mesher order
• mesne profits
• messuage
• MHRA
• MIAM
• Michaelmas Day
• micro-entity
• micro-state
• Middle Temple
• Midsummer Day