From Longman Dictionary of Contemporary Englishoff-airˌoff-ˈair adjective [only before noun] not being broadcast on the radio or television at the present moment OPP on air, on-air off-air television recordings
Examples from the Corpus
off-air• This is one example of a task related to an extract from off-air documentary material within a unit on drugs.• The treatment of off-air material outlined in Video Plans 14 and 15 could form the basis for discussion of this kind.• In some cases a single aerial serves a block of flats or a valley area where off-air reception is poor.• However you will need to find out about the laws governing off-air recording in the country you are in. 