From Longman Dictionary of Contemporary Englishinfra-redinf‧ra-red /ˌɪnfrə ˈred◂/ adjective CCTPinfra-red light gives out heat but cannot be seen → ultraviolet
Examples from the Corpus
infra-red• Thus, these gases act like the glass in a greenhouse, which similarly inhibits the loss of infra-red.• Herschel had found the infra-red detected invisible light in the form of radiant heat.• Each Mouse Alert system comprises a network of up to 360 strategically placed infra-red electronic sensor boxes.• In the transmitter, infra-red is modulated to carry the analogue sound information which then fills the room.• The ones with infra-red night-sights, little flashing digital displays, electric zooms and whatnots.• Note that a red l.e.d. is used rather than an infra-red one.• As mentioned earlier the warm-white lighting contains little infra-red radiation.• Some weapons home in on infra-red sources, some on radar, others just go where they are told. 