1. relating to or denoting electromagnetic radiation with wavelengths longer than those of red light, especially infrared radiation
Usage: technical; physics

Examples

• The ultrared radiation from the heat lamp warmed the reptile enclosure.
• Scientists use ultrared imaging to detect heat signatures in the dark.
• The telescope can capture both visible light and ultrared wavelengths.
• Ultrared photography reveals temperature differences invisible to the naked eye.
• The military uses ultrared sensors for night vision equipment.
• Astronomers study ultrared emissions from distant stars and galaxies.