The a&b in this term are actually numbers describing two equal-temperaments, and the ampersand symbol & always appears between the numbers in place of the word "and". See definition below.
I have a precise definition for this, but other people are more loose about it.
In my usage, a&b, for positive integers a and b and prime limit p, is the temperament defined by the wedgie for the patent vals for a and b in the prime limit p.
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