I turned next to the British National Corpus which had a paltry 13 instances of 'reawaken' and none of 'rewaken'; not much to go on. Now Google's first hit was Merriam-Webster Online, which suggested to me that this was an American English option; so I went to COCA. COCA had 90 'reawaken's, which gave me high hopes for 'rewaken'; but again there was none. (I suppose that makes sense: Google has over 1,000,000 'reawaken's - over 400 times as many as 'rewaken's; so a mere 90 hits for 'reawaken' don't even suggest a milli-hit for 'rewaken)'.
Merriam Webster puts the first recorded use of 'rewaken' at 1638, and the first recorded use of 'reawaken' goes unrecorded amongst all the other 're-' words. For what it's worth. the Online Etymological Dictionary dates 're-' to c. 1200. Anyway, 'rewaken' seems to be going out of fashion (like many of the poor relations in such pairs, dealt with by David Crystal in The Story of English in 100 Words under the headword 'Yogurt' - which isn't a member of a pair so much as a gaggle:
The first recorded usage [early 17th century] is yoghurd. Then we get yogourt, then yahourt, yaghourt, yogurd, yoghourt, yooghort, yughard, yughurt and yohourth. In the 19th century, there was a trend to simplify, and yogurt emerged as the front runner.
Some words just have poor relations, much less common and with a different spelling. And for all the attempts of the cognoscenti to make distinctions - the dear old OUP insists in the Oxford Dictionary for Writers and Editors that an enquiry is just a question and an inquiry is an institution formed to ask and investigate a particular line of questioning ('a polite enquiry' but 'a public inquiry') - those distinctions are largely ephemeral.
Which reminds me: -ise and -ize... But that will have to wait for another time. Some more harmless drudgery calls - Now where had I got to: 'reawaken, recreate, rectilinear...'
+ various updates to the footer, the most recent being on 2013.10.06.12:05
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