"Caveat" as a verb referring to a particular type of parry is in the OED, but with only one citation in use (Urquhart 1652, not independently verifiable). Only use I have been able to find is from Castle, 1885: "The attacks are delivered by caveating in all the lines, by falsifying singly or doubly, by battery or by binding. " . "Counter-caveating"/"contra-caveating" has a few more, but is really a distinct term.
If we do include it, we will need to determine whether it is in fact from the same Latin root, as the OED implies, or is instead a corruption of the Italian cavazione, as many fencing writers have asserted...  -- Visviva 09:18, 18 August 2009 (UTC)
I updated the pronunciations to better reflect the audio samples (which are, to the best of my knowledge, correct). The US pronunciation as given by the audio sample matched the UK pronunciation IPA definition, not the US pronunciation IPA definition. The UK audio sample has an ɛɹ in it.
Previous pronunciation keys:
I was able to find a reference to the previous US pronunciation at dictionary.cambridge.org—ironically, a UK-oriented site. However, the syllable breakup is wrong, so I suspect that the source is unreliable. Another site lists it as a secondary pronunciation (localization unspecified).
The UK pronunciation was previously ordered first. As I cannot find any official reference to a unique UK pronunciation other than the audio sample, I have ordered it second. Hopefully someone else can verify or correct the UK pronunciation.