1. Dutch astronomer who proved that the galaxy is rotating and proposed the existence of the Oort cloud (1900-1992)
   - Oort

Type of: astronomer, stargazer, uranologist

• flacourtia family
• Flacourtia indica
• Flacourtiaceae
• flag
• flag captain
• Flag Day
• flag down
• flag of truce
• flag officer
• flag rank
• flag smut
• flag smut fungus
• flag stop
• flag-waver
• flag-waving
• flagellant
• Flagellata
• flagellate
• flagellate protozoan
• flagellated
• flagellated cell
• flagellated protozoan
• flagellation
• flagellum
• flageolet