a. [L., = sick.] The L. word for ‘sick,’ used at the Eng. universities in excusing absence on account of illness; hence, a note certifying that a student is ‘æger’ or sick.

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1865.  Cornh. Mag., Feb., 227. A very common method of escaping the tedium of this duty … is ‘to send in an æger;’ in other words, to improvise an attack of illness.

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