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

Encyclopedia: Rocket science

• relative frequency
• relative humidity
• relative incidence
• relative majority
• relative molecular mass
• relative pronoun
• relative quantity
• shoe industry
• shoe leather
• shoe polish
• shoe repairing
• shoe shop
• shoe store
• shoebill
• shoebird
• shoeblack
• shoeblack plant
• shoebox
• shoed
• shoeful
• shoehorn
• shoelace
• shoeless
• shoemaker
• shoemaker's last