We found 7 dictionaries that define the word infrared rays:

General (2 matching dictionaries)

1. infrared rays: Vocabulary.com
2. Infrared rays: Wikipedia, the Free Encyclopedia

Business (1 matching dictionary)

3. BusinessDictionary.com (No longer online)

Medicine (3 matching dictionaries)

4. Dorland's Illustrated Medical Dictionary (No longer online)
5. Medical Dictionary (No longer online)
6. online medical dictionary (No longer online)

Tech (1 matching dictionary)

7. AUTOMOTIVE TERMS (No longer online)

(Note: See infrared_ray as well.)

Definitions from WordNet (infrared ray) ▸ noun:  a ray of infrared radiation; produces a thermal effect (as from an infrared lamp) ▸ Also see infrared_ray ▸ Words similar to infrared rays ▸ Usage examples for infrared rays ▸ Idioms related to infrared rays ▸ Wikipedia articles (New!) ▸ Words that often appear near infrared rays ▸ Rhymes of infrared rays ▸ Invented words related to infrared rays