1. An imaginary line connecting points on the Earth's surface where the magnetic declination is the same
   - isogonic line, isogone

Derived forms: isogonal lines

Type of: line

• erg
• ergo
• ergocalciferol
• ergodic
• ergodicity
• ergometer
• ergonomic
• ergonomically
• ergonomics
• ergonovine
• ergosterol
• ergot
• ergotamine
• ergotic
• ergotism
• Ergotrate Maleate
• ergotropic
• ergotropism
• Ergun He
• Erianthus
• Erianthus ravennae
• Eric Arthur Blair
• Eric Blair
• erica
• Erica arborea