(plural, op-ti-mes), in Cambridge phraseology, is a graduate in honours below a wrangler. Of course, the Latin optimus (a best man) is the fons et origo of the term. Optimës are of two grades: a man of the higher group is termed a senior optimë, while one of the inferior class is called a junior optimë.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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