Synonyms: infrared, infrared frequency
Definition: the infrared region of the electromagnetic spectrum; electromagnetic wave frequencies below the visible range
Usage: they could sense radiation in the infrared
Similar words: frequence, frequency, oftenness
Definition: the number of occurrences within a given time period
Usage: the frequency of modulation was 40 cycles per second; the frequency of his seizures increased as he grew older
Synonyms: infrared, infrared emission, infrared light, infrared radiation
Definition: electromagnetic radiation with wavelengths longer than visible light but shorter than radio waves
Similar words: actinic radiation, actinic ray
Definition: electromagnetic radiation that can produce photochemical reactions
Synonyms: infrared
Definition: having or employing wavelengths longer than light but shorter than radio waves; lying outside the visible spectrum at its red end
Usage: infrared radiation; infrared photography
Similar words: unseeable, invisible
Definition: impossible or nearly impossible to see; imperceptible by the eye
Usage: the invisible man; invisible rays; an invisible hinge; invisible mending