1. One of certain narrow, crooked valleys seen, by aid of the telescope, on the surface of the moon

Derived forms: rilles

Encyclopedia: Rille

• gym rat
• gym shoe
• gym suit
• gymkhana
• Gymnadenia
• Gymnadenia conopsea
• Gymnadenia odoratissima
• Gymnadeniopsis
• gymnasium
• gymnast
• gymnastic
• gymnastic apparatus
• gymnastic exercise
• gymnastic horse
• gymnastically
• gymnastics
• Gymnelis
• Gymnelis viridis
• Gymnocalycium
• Gymnocarpium
• Gymnocarpium dryopteris
• Gymnocarpium robertianum
• Gymnocladus
• Gymnocladus dioica
• Gymnogyps