1. The lowest region of the ionosphere (35 to 50 miles up) that reflects low-frequency radio waves
   - D region

Type of: part, region

Part of: ionosphere

Encyclopedia: D-layer

• Sandwich Islands
• sandwich plate
• sandwichman
• sandwort
• sandy
• sandy mushroom
• sane
• sanely
• saneness
• sanfoin
• sang
• sang-froid
• sangam
• sangapenum
• sangaree
• Sangay
• Sanger
• Sango
• sangoma
• Sangraal
• sangria
• sanguification
• Sanguinaria
• Sanguinaria canadensis
• sanguinary