The Wiktionary entry that TRex links to gives the following two meanings:
1. (transitive) To broadcast (a television programme, etc.) again.
2. (transitive) To air or let forth again.
to reair one's grievances
I couldn't see it in any other dictionary.
I think I would write it as
re-air if I were using it. The string of three vowels in
reair looks a bit too odd. Evidently other people agree: the News on the Web corpus has 16 instances of
reair and its inflected forms, and 540 instances of
re-air and its inflections. Strangely enough, I couldn't find the hyphenated version in any dictionary.
Nevertheless, adding
re to the front of the verb
air is a valid construction, and yields a meaningful word, which some people have used. It's mostly used in the rebroadcast sense. E.g. "The subject of Saturday's 'Four Sides of the Story' special, which reairs Monday at 7 p.m. on CBS Sports Network..."
An example of the other meaning was in the Irish online newspaper Extra.ie in March, where a photo of Michael Jackson is captioned, "Jackson died in 2009 but child sex abuse allegations against are now being reaired."
I'll add
reair,
reaired and
reairing as rare words.
