1. (informal) anything complex, detailed or confusing 
2. The science or study of rockets and their design

Encyclopedia: Rocket science

• rehearse
• reheat
• reheel
• rehire
• Rehnquist
• rehouse
• rehydrate
• Reich
• Reichstag
• Reichstein
• Reid
• reification
• reify
• reign
• Reign of Terror
• reigning
• reignite
• reiki
• reimbursable
• reimburse
• reimbursement
• reimport
• reimpose
• reimposition
• Reims